URBANA ILLINOIS STATE GEOLOGICAL SURVEY 3 3051 00000 1978 Coal No. 6 near Christopher, Franklin County. STATE OF ILLINOIS DEPARTMENT OF REGISTRATION AND EDUCATION DIVISION OF THE STATE GEOLOGICAL SURVEY M. M. LEIGHTON. Chief BULLETIN NO. 56 ILLINOIS COAL A Non-Technical Account of Its Occurence Production and Preparation BY A. BEMENT PRINTED BY AUTHORITY OF THE STATE OF ILLINOIS URBANA, ILLINOIS 1929 REPRINTED, 1932 STATE OF ILLINOIS DEPARTMENT OF REGISTRATION AND EDUCATION M. F. Walsh, Director BOARD OF NATURAL RESOURCES AND CONSERVATION M. F. Walsh, Chairman Edson S. Bastin, Geology Henry C. Cowles, Forestry William A. Noyes, Chemistry Charles M. Thompson, Representing John W. Alvord, Engineering the President of the University of William Trelease, Biology Illinois THE STATE GEOLOGICAL SURVEY DIVISION M. M. Leighton, Chief Jeffersons Printing & Stationery Co. Springfield, Illinois 1932 3i ; LETTER OF TRANSMITTAL State Geological Survey Division, December 2, 1931. M. F. Walsh, Chairman, and Members of the Board of Natural Resources and Conservation, Gentlemen : The first edition of our educational bulletin on "Illinois Coal: A Non- Technical Account of its Occurrence, Production, and Preparation" has be- come exhausted. This bulletin was prepared primarily for the public rather than the technical reader, with the hope that it would answer authoritatively many questions which arise in the minds of the citizens of our State and others regarding the Illinois Coal Field, which is the source of our most im- portant mineral industry. A second edition is now necessary to meet the demand for this popular bulletin and I therefore recommend its reprinting. Very respectfully, Morris M. Leighton, Chief. Digitized by the Internet Archive in 2012 with funding from University of Illinois Urbana-Champaign http://archive.org/details/illinoiscoalnont56beme CONTENTS Page Chapter I — General features of the Illinois coal field 13 Early discovery 13 Original coal resources 13 Productive coal seams 13 Modern coal mines 15 Coal sizing 19 Coal shipments within the State 21 Proportion of coal recovery 21 Mining districts 21 Variations in production 24 Chapter II — Geology of the Illinois coal field 29 Divisions of the Pennsylvanian system 29 Pottsville formation 30 Carbondale formation 31 McLeansboro formation 31 Nomenclature of Illinois coal seams 31 Structure of Illinois coal field 32 LaSalle anticline 32 Duquoin anticline 34 Faulted belt across southern Illinois 34 Illinois Ozarks 35 Chapter III — Illinois coal resources and their future 36 Estimates of coal resources 36 Coal depletion 39 Conditions affecting coal recovery 40 Concentration of production in southern Illinois 40 Chapter IV — Coal producing districts 42 Total production by districts 42 Total production by counties 42 County leadership 44 Wilmington district 45 Third Vein (LaSalle) District 46 Fulton-Peoria District 50 Springfield District 51 Grape Creek District 52 Central Illinois District 52 Centralia District 55 Franklin-Williamson District 56 Big Muddy District 58 Saline County District 59 7 Chapter IV — continued Page Other coal producing areas 50 Perry County 50 Vermilion County 51 Rock Island and Mercer Counties 61 Livingston County 61 Christian County 61 Moultrie County 61 McLean County 61 Macon County 62 Henry County , 62 Grundy County 62 Chapter V — Coal mining in Illinois 63 Mine openings .' 63 Depths of shafts 63 Mine data 65 Interpretation of mine data 65 Coal stripping 66 Chapter VI — Prepared coal 70 Introduction 70 Preparation of coal at the mine 70 Development of present methods of preparation 70 Preparation equipment 74 Preparation of small sizes 77 Marketing of prepared coal 79 Use of prepared coal 79 Small-size coal as stoker fuel 79 Research in the use of small sizes 80 Reasons for range in performance of small sizes 81 Comparative performance of screenings and small prepared sizes 85 Chapter VII — Analyses of coal 86 Origin and physical character of coal 86 Chemical character of coal 86 Coal analyses 86 Proximate analyses 86 Methods used in obtaining chemical data on Illinois coal 87 Moisture in coal 87 Ash 88 Volatile matter and fixed carbon 90 Sulphur 90 Heat Calories (B. t. u.) 92 Importance of accurate B. t. u. determinations 92 Determining fuel values 93 Ultimate analyses of coal 94 Combustible and noncombustible ingredients 95 Constant and variable elements in coal 95 Standard calorific values — ash- and moisture-free coal and unit coal 97 B. t. u. value of carbon, hydrogen, and sulphur 98 Analyses 99 Index 115 ILLUSTRATIONS Figure Page Frontispiece A thirteen-foot bed of No. 6 coal in Franklin County, Illinois 1. Joliet's map of 1674 12 2. Surface equipment of the largest coal mine in the world 14 3. Rotary car-dumper at shaft bottom 16 4a. Main hoist at an electrically operated mine 16 4b. Motor generator set used in operating hoist 17 5. Air shaft end of a modern mine in Saline County 17 6a. Loading side of shaft bottom 18 6b. Empty car side of shaft bottom 18 7. Surface equipment of a modern mine in Franklin County 20 8. Map showing distribution of the principal coal seams 22 9. Map showing location of the principal trade districts 23 10. Map showing location of coal production in 1880 24 11. Map showing location of coal production in 1925 25 12. Graph showing average curve of coal production for the entire State 26 13. Graph showing average curves of production for northern, central, and southern Illinois 27 14. Graph showing average percentage curves of production, based on State totals, for northern, central, and southern Illinois 28 15. No. 6 coal and associated strata near Brereton, Fulton County 30 16. Dipping strata on the west flank of the LaSalle anticline 33 17. Plan of room-and-pillar mine 47 18. Plan of longwall mine 48 19. Dump heap from a longwall mine 49 20. Spring Valley Mine No. 5, now dismantled 50 21. A "horseback" or clay vein in a coal seam 51 22. Plan of panel mine 53 23. Mining machine undercutting coal bed 54 24. Miners loading coal 55 25. Coal trains near the shaft bottom 56 26. Surface equipment of a mine in Franklin County 57 27. Airplane view of coal stripping operation in Vermilion County 67 28. Electric shovel used in coal stripping 67 29. Modern tipple at coal stripping mine in Fulton County, Illinois 68 30a. Lump coal — that retained on a 6-inch screen 71 30b. No. 2 nut coal — that which passes a 2-inch screen and is retained on a 1*4 -inch screen 71 31. Graph showing the percentage of lump coal produced 72 32. Graph showing increase in the use of powder to blast out the coal 73 9 Figure Page 33. Shaker screens used in making prepared sizes of coal 74 34. Picking tables where foreign matter is removed from the coal 75 35. Aduj stable loading conveyors 76 36. Battery of screens for the separation of small prepared sizes of coal 76 37. Tipple and washery at mine in Macoupin County 78 38a. Graph showing the effect of the size of coal screenings on efficiency of com- bustion in steam production 80 38b. Graph showing the effect of the size of coal screenings on capacity secured in steam production 81 39. Graph showing relation between over-size coal and ash-pit loss of unburned coal 82 40a. Graph showing comparison of performance of screenings and small prepared sizes of coal with reference to efficiency of combusion in steam production ... 83 40b. Graph showing comparison of performance of screenings and small prepared sizes of coal with reference to capacity secured during steam production 84 41. Graph showing per cent of ash in dry coal and efficiency obtained in steam production 88 42. Graph showing relation of sulphur content to fusion temperature of ash 89 43. Map showing location of low-sulphur coal in Illinois 91 44. Map of trade districts showing average B. t. u. values of the coal seams 96 10 TABLES Table Page 1. Nomenclature of principal Illinois coal seams 32 2. Estimate of Illinois coal areas and original resources 36 3. Original and present available resources of the trade districts 38 4. Depletion of coal in Williamson and Franklin counties 39 5. Production from corporation mines in 1925 40 6. Total production of trade districts from 1881 to 1930 42 7. Total production from Illinois counties from 1881 to 1930 42 8. Counties leading in coal production, 1881 to 1930 44 9a. Comparison of mine production for 1908 and 1925 64 9b. Comparison of mine labor for 1908 and 1925 64 10. Production of coal by stripping in 1926 66 1 1. Standard sizes of coal 70 12. Comparison of the effective fuel values of two coals 94 13. County averages of proximate analyses of Illinois coal 99 14. Average proximate analyses of coal from trade districts 105 15. County averages of ultimate analyses of Illinois coal (standard form) 108 16. County averages of ultimate analyses of Illinois' coal (amplified form) Ill 11 12 ILLINOIS COAL The Central Portion of Joliet's Map, 1674, Showing the Mississippi as the "Baude". Fig. 1. Copy of Joliet's map made in 1674. (From "A History of the Mississippi Valley," by Spears and Clark.) The arrow has been added by the editor to show the position of the notation, "Charbon de terre". ILLINOIS COAL A Non-Technical Account of its Occurrence Production and Preparation By A. Bement CHAPTER I— GENERAL FEATURES OF THE ILLINOIS COAL FIELD Early Discovery In many respects the Illinois Coal Field is a notable one. It was in Illi- nois that the first recorded discovery of coal was made on the North Ameri- can continent. Joliet and Father Marquette in their voyage of exploration in 1673 by way of the Illinois valley and Chicago River made the original dis- covery some place between the present cities of Utica and Ottawa. Only the approximate site is marked by the words "Charbon de terre" (coal) on Joliet's map of 1674, the central portion of which is reproduced in figure 1. The same "Charbon de terre" appears on Marquette's map of 1681, and on Henne- pin's map of 1689 a "cole mine" is shown on Illinois River above Fort Creve Coeur, now Peoria. Original Coal Resources When mining began in Illinois, the State contained more coal than any other state east of Missouri River, and indeed still contains much more un- mined coal than even that possessed by any other state in the territory at the time mining operations were begun. At the close of the Coal Measures period this was not true. At that time the eastern fields covered much more acreage and contained much more coal than the Central Interior field, of which the Illinois field forms the major part. The loss of this position by the eastern fields since that time was due to the Appalachian uplift, folding and elevating the rock strata to high exposed positions over large areas, where it has been subject to prolonged erosion and removal. What remained when mining began was but a fragment of the original. The Illinois field, however, was but slightly affected and still posses- ses most of the coal that was formed here during Coal Measures time, so that now this field has a commanding position with respect to available coal resources. Productive Coal Seams In the Illinois Coal Field there are but few seams of a sufficient thickness for profitable mining. Areas underlain by the principal seams are neverthe- 13 14 ILLINOIS COAL o U ,_, X fe rt O X M-l Crt 2 »H rt rt J-l fe , . V. en is ,r! i/ oJ I-H n" O o inches; 2-inch and 1^-inch screen- See Chapter VI on Prepared Coal. 20 ILLINOIS COAL +s TJ > P C/> P u O rp U Pi _, a; . ~ X M H c ^ oS 4J crt U< Ih u .5 rt T3 Jd a o rt CO cc ^j ►P Ih O ,__, Pi Pi P CO 1) > O > CO O Jh V u r^ X o 0> O fe GENERAL FEATURES OF THE COAL FIELD 21 ings. No. 2 nut is loaded on the same track as the 2-inch screenings, for when No. 2 nut is made no 2-inch screenings are produced. In this way six regular sizes of coal are loaded on five tracks. In Illinois mines making a full preparation (see Chapter VI), standard practice requires a re-screening plant to which l 1 /^ -inch screenings are con- veyed for separation and loading independent of the main tipple. Harco mine No. 7 at Harco, Saline County, is a unique example of a mine having a re-screening plant combined in a seven-track tipple which makes and loads nine standard sizes, three extra sizes in addition to those noted above. The extra sizes are : chestnut or No. 3 nut, \y 2 by Y\ inches ; pea, 24 by ^ inches ; and carbon, less than ^ inch. The No. 3 nut and the 1^4 -inch screenings are loaded on one track, and 2-inch screenings and No. 2 nut also on one track. Coal Shipments Within the State For nearly thirty years there has been a growing movement of coal from southern districts into other coal-producing districts within the State. For example, Decatur, with two mines in town which allow of direct delivery from shaft to consumer, imports southern coal. Likewise LaSalle and Peru, with a mine shaft on the main street of each town, purchase part of their domestic supply from the southern district, 250 miles away, and the electric power plant at LaSalle uses stoker fuel from the same source. The shift of production from north to south has been remarkable in view of the fact that northern fields are commonly nearest to market. Table 8 (p. 44) shows LaSalle County as the leader in production in 1881 ; the peak of production, moving south, reached Williamson County in southern Illinois in 1907, where it remained until Franklin County assumed the leadership in 1915. Proportion of Coal Recovery In Illinois mines about one-half the coal is unrecovered, the amount of recovery being much less than in the eastern fields. Low percentage of recovery is partly due to the necessity of leaving pillars in compliance with the demands of property owners. Extraction in the longwall field where no pillars are left represents about 95 per cent of the coal, but extraction by the room-and-pillar method is probably about 50 per cent. Mining Districts Figure 8 shows areas known to be underlain by the principal coal seams, and figure 9 outlines the ten general trade districts. The Big Muddy district has been worked out and is shown for historical reasons only. There has been no commercial underground mining for several years in the original Wilmington field, but this district is again producing because of the recent opening of a large stripping operation within its boundaries. 22 ILLINOIS COAL Early mining was confined largely to the northern and southwestern portions of the coal field. LaSalle and Grundy counties in northern Illinois and Madison and St. Clair counties in southern Illinois were particularly LEGEND HQIICoa! No. 2 \//A Coz\ No. 5 1=1 Coal No. 6 E5J3coal No.7 [s^l Generally un prospected Goal No. 2 and coals of uncertain age P(?beds) Fig. 8. Map of Illinois showing general distribution of principal coal seams 1 important in the production of coal. Madison and St. Clair counties originally furnished St. Louis with most of its coal supply. The only other important mining area was the Big Muddy District in Jackson County near the southern 1 Field investigations by Dr. H. B. Wilman in the summer of 1930 have shown that the coal in LaSalle, Bureau, and Putnam Counties mapped as No. 5 is probably coal No. 6. GENERAL FEATURES OF THE COAL FIELD 23 -extremity of the State. The No. 2 coal mined there furnished the best quality coal then produced in the State. Figures 10 and 11, which show the Illino is S tate Geolog cal Survey TRADE DISTRICTS 1. Wilmington. 2. Third Vein (LaSalle). 3. Fulton-Peoria. 4. Springfield. 5. Grape Creek. 6. Central Illinois. 7. Centralia. 8. Franklin -Williamson. 9. Big Muddy. 10. Saline County. Fig. 9. Map of Illinois showing the location of the ten principal trade districts. centers of production in 1880 and 1925 respectively, bring out strikingly the southward shift in production. 24 ILLINOIS COAL Variations in Production Figure 12 shows the average curve of annual production for the State as a whole from 1882 to 1925. The broken line indicates that if normal demand COAL PRODUCTION 1880 One million tons per year Coal field .boundary Fig. 10. Map of Illinois showing the location of mining and also the relative production from different localities in 1880. GENERAL FEATURES OF THE COAL FIELD 25 had continued to 1925, production would have reached 93,000,000 tons. In determining the normal curve the abnormal years of 1917, 1918, 1921, and COAL PRODUCTION 1925 Ten million tons per year Coal field boundary Fig. 11. Map of Illinois showing the location of mining and also the relative production from different localities in 1925. In comparing figures 10 and 11 the difference in production scale should be noted. 26 ILLINOIS COAL 1922 were not considered. The demand in 1917-1918 was due to the World War, 1921 was a year of exceptional industrial activity, and in 1922 there was a five month's interruption due to miners' strike. 1 1 1 ! If! - 1 l!| J / 90 1 i i 1 k . 1 "17 ! i? i_ ; 1 i ! i Lld-j i | 1 !'f ' 80 1 ih | i ( ► i ^i | 11' ' 1 ■ ! 1 j i ! 1 411 | 1 | i 70 ! 1 i i i > i i 1 i i . 4 ► / < » i » 60 " £ / 50 /, < > « / ► 4 > i_. i f ' > 4 »y « »/ 30 f /i i zo I l i » S -d r 10 < >_J r"1 1 1 n 188£ &5 88 91 94 09 21 Z4 Fig. r 1900 03 06 YEARS 12. Average curve of Illinois coal production in millions of tons from 1882 to 1925. The dotted line shows what would have been attained if the normal trend had continued. Dots 17, 18, 21 and 22 were ignored in plotting the upper part of the curve for they represent productions of abnormal years, 1917 and 1918 being the years of the World War, 1921 a year of abnormal demand, and 1922 a year of five months' suspension due to labor trouble. Figure 13 shows the average curves of production for three parts of the State, northern, central, and southern, in which Sangamon County is consid- GENERAL FEATURES OF THE COAL FIELD 27 ered typical of the central portion. Figure 14 shows the average percentage curves, based on State totals, for the same three divisions. These two graphs picture rather strikingly the change in leadership in production from north to south. The northern districts, where the longwall method of mining is em- 1 1 | 35 - 30 ( ) ... | . ( ) . — t ~) C \, ' \ ) V / /' (. ) A ) eo , / 1 / j 1 {< ) 1 / J 15 / / ' / 10 '< ' c ) C ) / / « » (. J / ! ... „ ^ k / *.* > : i : 3 5 "^! l^ : ~~ 1 i • .- '7 V a_ >-i 1 < 1 ; :h H L, » "i i < » - J r ^ f X J „ t ^ — r; !*" J H* ^ r i *N ^ |q c._> <_- •-■ f t- ^M M M t>- y 18 &z e 5 £ B 9 l s 4 9 7 19 00 C 3 6 9 1 I i 5 1 8 I \ Z 4 YEARS Northern Illinois. Sangamon County. Southern Illinois. Fig. 13. Average curves of production for Northern Illinois (Third Vein and Wilmington districts), Sangamon County, and Southern Illinois. ployed, although nearer the large markets, have not been able to compete with the lower cost of production and the better coal from the southern districts It appears from figure 14 that the increase of production in southern Illinois has been greater since 1922 than previous to that time, but by refer- 28 ILLINOIS COAL ence to figure 13 it may be seen that the actual increase was very slight, that the district has no more than maintained its rate of production and that the 4S " __ T__ "~ - - - 45 ___ t - ._ _ .... . ~j_ 40 - _ -. ' " ' T~ f . ... . _. | .. ... _ _ jA.^- o l/ () >7 35 "_+_ i. _| : - ~ - ' - ~ . , A* r n /" k __4-;r»_ : ^-^- N^ / ii^ ° ' ' ~^t '" --^- ^e- ^ - - - - - -^r-t- -+\- -^s -^ttr**- ■' ^ai^^w^ ,_ ^ ^< ( ^&_ x -'■^-:r-,-'-. r .^' 1 ^ ^ *" -' :: -. N h ^O M K N NO p On «-H > V u 0J LO lo r^ o r^ o u-j ^f • LO ON ON M" LO LO LO LO Ph o o CD bjo .S3 o 'O lO 't CVJ K O CO C\J rsJ C ^J- LO CM co vo CM CO CM ' On oo ON_ ^ LO^ Tf O LO co" no" tC lo" t-T 00^ . CM rC • t-T CO c Jh i c M K O rt oo O O0 • co CM • ON On • t-h CO ft o in m N 00 C\ T(- \0 t-h CM CM t-h r^ C Q ,_,- o o r-l "O" 03 . oo no r^ lo Jh tO "*" no" rC no" t-h" CO 00" • t-h" 1-1 1 J u 3 ^ £ H ~ fe co O U U fe ~ PQ co r-i CM co ^ lo no K oo On O T-H ^ < RESOURCES AND THEIR Fill Kl 39 Coal Depletion The State Department of Mines and Minerals reports that of the original resources 2,041,691,288 tons were mined in the period 1882 to 1930 inclusive, and that the government estimate for coal mined from 1833 to 1882 is 73.341,123 tons, which gives a total production of 2,115,032,411 tons. On the basis of the above figures and a 50 per cent recovery the entire held has been depleted by 4,230,064,822 tons, or only 2.1 per cent. However, as mining for a long time will be confined to the trade districts shown in fig- ure 9, mining it these districts is the problem of present concern. Table No. 3 gives an approximate measure of available resources, applied to what may be considered the immediate as distinct from the remote future. From this table it appears that depletion outside of the southern Illinois territory (excepting Grape Creek and Big Muddy Districts) is between 3.5 and 5 per cent, whereas in the newer districts of southern Illinois depletion is 10 and 12 per cent. In District No. 8 depletion is 10.6 per cent, notwith- standing the fact that Franklin County has come into production only in recent years and that thus far Jefferson County has produced comparatively little coal. The situation, as applied to Williamson and Franklin counties, is shown by the figures in Table 4. Table 4. — Depletion of coal in Williamson and Franklin counties Square miles Millions of Tons Percentage of County Coal per square mile Original resources Coal mined Deple- tion Coal re- maining Recovery Depletion Williamson. . Franklin. . . . 185 385 8.80 11.00 1,628 4,235 210 224 389 533 1,239 3,702 54 42 23.8 12.6 a Allen C. A., Coal losses in Illinois: Illinois State Geol. Survey Coop. Min. Ser. Bull. 30, 1925. If it is assumed that Williamson County for the next twenty years will average 8,000,000 tons a year, the production for the period will be 160,000,000 tons; and depletion of 296,300,000 tons plus previous depletion will give a depletion by the year 1950 of 682,300,000 tons, or about 42 per cent depletion by that time. 40 ILLINOIS COAL Conditions Affecting Coal Recovery Recovery in trade districts Nos. 1 and 2 is about 95 per cent. In other districts where the room-and-pillar method of mining is practised, recovery is sometimes as high as 60 to 70 per cent, but in every district there are areas that are not mined. For example, coal is seldom mined from under a ceme- tery, and generally it is not mined under towns or cities. There are also many places where the original owners of the coal for various reasons refuse to sell or lease to mining companies engaged in gathering a field. These areas are usually small, they become surrounded by operated territory, and are left when the mine is worked out. As they are too small to justify separate oper- ation they remain unmined. For several reasons unworked territory is often left in mines and separating mines. A 50 per cent recovery may therefore be considered an average figure for those trade districts in which the room- and-pillar method is used. Concentration of Production in Southern Illinois It was not until about the year 1907 that coal users began seriously to consider southern Illinois as a source of supply. By 1925 Williamson, Frank- lin, and Saline counties produced 41 per cent of the State's output, an in- crease of 380 per cent over that of 1907, accompanied by diminished produc- tion in all other districts. It appears probable that coal production from southern Illinois will continue to increase and that there will be a correspond- ing decrease in other districts. However, the more concentrated the produc- tion in southern Illinois the shorter will be the life of the southern territory and the sooner will production be restored to the districts which are now being abandoned, but which sometime in the not very remote future will again be valuable property. This is probably not a matter of critical interest to the general public but it should be a matter of concern to those industrial organizations who must consider adequate fuel supplies for their future. Corporations such as railroads or public utilities, which are permanent institutions, are justified in providing for the future, and a number of such corporations have acquired coal lands, particularly in Central Illinois District. Production from such properties for the year 1925 was as follows : Table 5. — Production from corporation mines in the Central Illinois District in 1925 Tons Produced County Corporation Mines County Total Christian 3,380,431 4,410,885 1,444,375 800,651 3,823,214 Macoupin . 6,213,109 Montgomery Jackson 2,156,726 1,497,263 RESOURCES AND THEIR FUTURE 41 RESOURCES AND THEIR FUTURE In 1925 the output from these properties together with that from similar mines in counties other than those of southern Illinois, was 14,170,020 tons. Production for that year from all shipping mines in the State was 64,180,414 tons. Subtracting the output of corporation mines, the production of what may be classed as strictly commercial mines was 50,010,394 tons. Of this the 27,000,000 tons from Southern Illinois District forms 54 per cent. A por- tion of the product of corporation mines finds an outlet in the commercial market in the form of larger sizes, 6 by 3 or 3 by 2 inches. Corporations which use stoker fuel and sell some of the larger coal have a lower cost stoker fuel than they would have if the larger coal were crushed. Much of the coal is necessarily crushed, however, because the market for the large coal is restricted. If the management of some of these corporations should decide as a measure of economy to- buy coal produced in southern Illinois and hold their fields as a reserve for the future, this would be a considerable factor, in addi- tion to the present increasing demand, in curtailing the life of the southern field. CHAPTER IV— COAL PRODUCING DISTRICTS Total Production by Districts The Illinois coal field is divided into ten trade districts, as outlined in figure 9, page 23. The part played by the districts in the coal industry of Illinois has varied notably from time to time. The total production for each district from 1881 to 1930 is given in Table 6. Table 6. — Total production by trade districts 1881-1930" District Coal No. Production in tons 1 Wilmington 2 48,316,663 2 Third Vein (LaSalle) 2 144,207,658 3 Fulton-Peoria 5 130,592,256 4 Springfield 5 140,672,436 5 Grape Creek 6 109,926,849 6 Central Illinois 6 874,729,287 7 Centralia 6 33,107,484 8 Franklin-Williamson 6 436,510,371 9 Big Muddy 2 29,000,000 10 Saline County (Saline-Gallatin) 5 104,376,173 a Computed from compilation of the coal reports of Illinois, 1882-1930: Dep't Mines and Minerals, p. 16, 1931. Total Production by Counties In order that the reader may review the history of production by coun- ties in the order of tonnage the data have been assembled in Tables 7 and 8. Table 7 shows the total production by counties for the period 1881-1930, listed both alphabetically and by rank. Table 7. — Total production from Illinois counties 1882-1930 inclusive 0. Alphabetical Order Order of Tonnage County Total Tons Rank Rank County Total Tons Bond 6,536,721 32 1 Franklin 224,503,106 Bureau 46,268,256 14 2 Williamson 210,779,985 Cass 200,135 50 . 3 Sangamon 183,535,854 Christian 77,669,381 9 4 Macoupin 173,985,244 Clinton 32,720,868 19 5 St. Clair 153,043,660 Edgar 177,459 51 6 Madison 117,257,007 Franklin 224,503,106 1 7 Vermilion 109,926,849 Fulton 66,458,445 11 8 Saline 101,361,807 Gallatin 3,015,366 37 9 Christian 77,669,381 42 PRODUCING DISTRICTS 43 ( ounty Greene Grundy Hancock . . . Henry Jackson Jefferson Jersey Johnson Kankakee . . . Knox LaSalle Livingston . . . Logan Macon Macoupin . . . McDonough . McLean Madison Marion Marshall . . . Menard Mercer Montgomery . Morgan Moultrie Peoria Perry Putnam Randolph Rock Island . St. Clair .... Saline Sangamon . . . Schuyler Scott Shelby Stark Tazewell Vermilion . . . Warren Washington . Will Williamson . . Woodford . . . Other counties Alphabetical Order Total Tons 466,076 .... 37,739,265 281,454 5,953,806 . . . . 41,730,547 1,227,280 102,041 236,847 1,951,778 2,984,499 . . . . 59,354,000 9,874,199 13,343,640 9,516,334 . . . . 173,985,244 2,483,744 5,534,589 .... 117,257,007 . . . . 33,107,484 .. 12,401,103 . ... 11,531,386 . . . . 14,641,853 . . . . 61,718,866 160,236 2,032,236 . ... 44,159,181 .... 68,711,924 9,587,284 . . . . 31,350,133 3,316,475 . . . . 153,043,660 . . . . 101,361,807 . . . . 183,535,854 810,608 579,692 3,869,507 1,037,376 . . . . 13,695,779 . . . . 109,926,849 566,255 .... 10,921,685 8,625,620 . . . . 210,779,985 6,722,816 1.923,551 Rank 47 17 48 33 16 42 53 49 41 38 13 27 23 29 4 39 34 6 18 24 25 21 12 52 40 15 10 28 20 36 5 8 3 44 45 35 43 22 7 46 26 30 2 31 Rank Order of Ton nag County 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 Perry Fulton Montgomery LaSalle . . . Bureau Peoria Jackson . . . Grundy Marion Clinton Randolph . . Mercer Tazewell . . Logan Marshall . . Menard . . . Washington Livingston . Putnam . . . Macon .... Will Woodford . Bond Henry McLean . . . Shelby .... Rock Island Gallatin . . . Knox McDonough Moultrie . . Kankakee . Jefferson . . Stark Schuyler . . Scott Warren . . . Greene .... Hancock . . Johnson . . . Cass Edgar Morgan . . . Jersey Total Tons 08,711,924 66,458,445 61,718,866 59,354,000 46,268,256 44,159,181 41,730,547 37,739,265 33,107,484 32,720,868 31,350,133 14,641,853 13,695,779 13,343,640 12,401,103 11,531,386 10,921,685 9,874,199 9,587,284 9,516,334 8,625,620 6,722,816 6,536,721 5,953,806 5,534,589 3,869,507 3,316,475 3,015,366 2,984,499 2,483,744 2,032,236 1,951,778 1,227,280 1,037,376 810,608 579,692 566,255 466,076 281,454 236,847 200,135 177,459 160,236 102,041 Total 2,041,691,288 a A compilation of the reports of the mining industry of Illinois from the earliest records to the close of the year 1930: Dep't of Mines and Minerals, p. 16, 1931. 44 ILLINOIS COAL County Leadership Table 8 shows which county led in production for each of the years from 1881 to 1930 and shows the southward shift in production illustrated in figures 10-11 (pp. 24, 25) and 13-14 (pp. 27, 28). Table 8. — Counties leading in coal production Chronological Order Year County Tons 1881 LaSalle 624,900 1882 LaSalle 2,365,000 1883 Macoupin 1,233,200 1884 Macoupin 1,164,409 1885 St. Clair 1,202,549 1886 Macoupin 1,085,539 1887 LaSalle 1,125,235 1888 St. Clair 1,184,579 1889 Macoupin 1,202,187 1890 Macoupin 1,369,919 1891 St. Clair 1,595,839 1892 Macoupin 1,823,136 1893 St. Clair 2,133,870 1894 St. Clair 1,623,684 1895 Macoupin 1,948,992 1896 Macoupin 2,097,539 1897 Vermilion 2,000,623 1898 Sangamon 1,763,863 1899 Vermilion 2,221,867 1900 Sangamon 2,519,911 1901 Sangamon 2,919,223 1902 Sangamon 3,672,987 1903 Sangamon 4,386,526 1904 Sangamon 4,516,358 1905 Sangamon 4,395,050 1906 St. Clair 4,168,019 1907 Williamson 5,266,452 1908 Williamson 5,367,140 1909 Williamson 5,869,757 1910 Williamson 5,858,413 1911 Williamson 5,212,749 1912 Williamson 7,086,554 1913 Williamson 7,709,110 1914 Williamson 7,710,740 ■ 1915 Franklin 7,324,644 1916 Franklin 9,070,811 1917 Franklin 11,317,657 1918 Franklin 12,007,397 1919 Franklin 11,332,912 1920 Franklin 11,299,280 coal producti on, 1881-1930 Tonnage Order County Year Tons Franklin . . , 1926 15,741,550 Franklin . . . 1929 14,819,448 Franklin . . , 1928 14,078,932 Franklin . . . 1925 13,082,622 Franklin . . . 1923 12,845,459 Franklin . . . 1921 12,723,700 Franklin . . . 1924 12,240,925 Franklin . . . 1918 12,007,397 Franklin . . . 1930 11,997,347 Franklin . . . 1919 11,332,912 Franklin . . . 1917 11,317,657 Franklin . . . 1920 11,299,280 Franklin . . . 1927 10,360,881 Franklin . . . 1922 9,999,917 Franklin . . . 1916 9,070,811 Williamson 1914 7,710,740 Williamson 1913 7,709,110 Franklin . . . 1915 7,324,644 Williamson 1912 7,086,554 Williamson 1909 5,869,757 Williamson 1910 5,858,413 Williamson 1908 5,367,140 Williamson 1907 5,266,452 Williamson 1911 5,212,749 Sangamon . 1904 4,516,358 Sangamon . 1905 4,395,050 Sangamon . 1903 4,386,526 St. Clair . . . 1906 4,168,019 Sangamon . 1902 3,672,987 Sangamon . 1901 2,919,223 Sangamon . 1900 2,519,911 LaSalle . . . 1882 2,365,000 Vermilion . 1899 2,221,867 St. Clair . . . 1893 2,133,870 Macoupin . . 1896 2,097,539 Vermilion . 1897 2,000,623 Macoupin . . 1895 1,948,992 Macoupin . . 1892 1,823,136 Sangamon . 1898 1,763,863 St. Clair .. 1894 1,623,684 PRODUCING DISTRICTS 45 Table 8 — concluded Year County Tons County Year Tons 1921 Franklin 12,723,700 St. Clair 1891 1,595,839 1922 Franklin 9,999,917 Macoupin 1890 1,369,919 1923 Franklin 12,845,459 Macoupin 1883 1,233^200 1924 Franklin 12,240,925 St. Clair 1885 1,202,549 1925 Franklin 13,082,622 Macoupin 1889 1,202,187 1926 Franklin 15,741,550 St. Clair 1888 1,184,579 1927 Franklin 10,360,881 Macoupin 1884 1,164,409 1928 Franklin 14,078,932 LaSalle 1887 1,125,235 1929 Franklin 14,819,448 Macoupin 1886 1,085,539 1930 Franklin 11,997,347 LaSalle 1881 624,900 Wilmington District Although this district is called the Wilmington District the coal actually occurs to the west of that town. (See fig. 9, p. 23.) Parts of Will, Kan- kakee, Grundy, and Livingston counties are included. During early produc- tion coal from the No. 2 seam was shipped from Braidwood, Braceville, and Morris, and large amounts were sent to Chicago 1 , sixty-five miles away. Notwithstanding the proximity to such an important coal-using center, con- ditions have so changed that shipment from the No. 2 seam of the Wilmington District has entirely ceased, although two small mines produce a little coal for local use. 1 The No. 2 coal in the Wilmington District averages about 3 feet thick, and early mining was by the longwall method. (See discussion of Third Vein [LaSalle] district for description of this method.) The first mining was by slopes along the outcrop and later by shafts, as mining moved back from the outcrop. Essentially all of the coal is removed in mining by the longwall sys- tem, but with the coal is hoisted a considerable amount of rock and dirt. This is dumped on the surface at the shaft where the accumulated debris forms a large mound. Many of these mounds, marking the sites of former mines, may be seen from the Chicago and Alton Railroad, and a few near Morris may be seen from the Rock Island Railroad. The spoil bank on the west side of Kankakee River at the Chicago and Alton Railroad bridge does not indi- cate a mine but was the site of a former coal washer. Other coal washing plants which obtained their water supply from abandoned mines were once operated in this district. 1 Since this bulletin was prepared a coal stripping project has been started in the No. 2 coal seam west of Wilmington. 46 ILLINOIS COAL Only a comparatively small amount of the coal of this district has been mined ; it is not worked-out, but is except for an important strip mine an abandoned field. Cost of production, as compared with the cost of working thicker seams, where the room-and-pillar method is used, is the chief reason for the decline. The digging of a farm well resulted in the chance discovery of an isolated body of workable coal, probably coal No. 7, near Verona, Grundy County, about 1920. After the area of coal had been outlined by careful drilling, a modern mine was opened which since 1923 has produced some 2,116,405 tons of coal, practically exhausting the supply. Relatively low production costs and freight rates favored the operation of the mine. Table 14, page 105, shows the average quality of coal from this district. Third Vein (LaSalle) District Portions of LaSalle, Bureau, Putnam, Marshall, Woodford, and Living- ston counties are included in this district — an extensive territory in which the No. 2 coal seam is uniformly present at a thickness of 3 to 3^2 feet. Although this coal bed is the same as that in the Wilmington district the two areas are separated by the LaSalle anticline, as described in Chapter II, and have always been recognized as distinct trade districts. The outcrop of the coal to the east of the city of LaSalle early invited mining and the first shaft in the district was sunk at the city. In those days, territory was not prospected by drilling ; instead the shaft was sunk until it reached coal, which may have been No. 6 or No. 7. This seam was mined for a time, then the shaft was sunk to No. 5 coal and still later to the No. 2 coal. These coals were called the first, second, and third "veins." The No. 2 seam is reached by shafts from 300 to 465 feet in depth, de- pending on the elevation of the surface from which the shaft is sunk, the deeper ones being located on the higher ground away from Illinois River. Just east of the city of LaSalle the anticline so elevated the seam that the coal is present only in the tops of hills south of Illinois River, although at LaSalle it lies some 500 feet lower. The longwall method of mining in the Third Vein and Wilmington districts is quite different from the room-and-pillar method practised in the thicker coal seams in other portions of the State. (See fig. 17.) In opening a mine under the longwall system a sufficient block of coal is left to support the shaft and plant (fig. 18) so that they will not be affected by settling of the ground. From this central point the coal is mined out in an ever-increasing circle, with passageways leading from the shaft to the face of the coal at con- venient intervals. As the removal of the coal does not provide enough head- PRODUCING DISTRICTS 47 \\nwnmZVfWffWfTfwl tJliiii ilniii iiiiiii L&iikuL rrrrrfrrf !■ Mini Iglllll I I Nil II III I II 1 1 Fig. 17. Plan of room-and-pillar mine 48 ILLINOIS COAL room, it is increased by removing with hand-pick some of the overlying- strata along the entries or roadways. The coal is also undercut by hand-pick in the fireclay below. The shale taken down in extending the entries and the under- cuttings from the clay are used to build up a pack wall a few feet behind the coal face to prevent undue settlement of the overlying strata. These pack walls Fig. 18. Plan of longwall mine. do not entirely prevent subsidence, for during the night enough pressure is exerted on the undercut coal to break it down so that when the miners arrive in the morning the coal is ready to be loaded out. In this manner the continu- ous face of coal, or longwall as it is called, moves out in a constantly widening circle, with the spaces behind, except the entries, filled to support the roof. PRODUCING DISTRICTS 49 By this method nearly all the coal is removed, and although the seam may be only 3 l / 2 feet thick the production per acre is as much as from a seam 7 feet thick mined by the room-and-pillar method with half of the coal left underground. Practically all the No. 2 coal has been mined from beneath LaSalle since the city was built. Due to the fact that so much of the coal is recovered in these northern fields they have occupied a notable position with respect to conservation of natural resources. From the standpoint of economy of operation these fields occupy a less notable position. Inasmuch as all the coal is removed, and as the packing ma- terial used to replace it is smaller in bulk, there is eventually permanent settling of the overlying strata. The packing serves to temporarily support the roof as mining progresses but eventually subsidence tends to close the passage- Fig. 19. A mound of refuse from the Longwall system of mining in the Third Vein (LaSalle) district. ways leading from the shaft to the coal face. These rriust be kept open to the proper height, so shale from the roof of the passageways above is removed, and together with that which falls, is loaded into mine cars and dumped at the surface, gradually forming large refuse mounds (fig. 19). In general about 20 per cent of the cars hoisted are loaded with material which goes to the dump. The expense of handling this waste material and the amount of labor required results in a cost of production higher than in the room-and- pillar mines in the other districts of the State. The mining plants in the Third Vein District were the best in Illinois in their day. Figure 20 shows a general type. This particular view is of the 50 ILLINOIS COAL Spring Valley Mine No. 5, which has since been dismantled, but when it was opened, about twenty years ago, it was the best equipped plant in the State. It seems reasonable to expect that this district, as well as the Wilmington District, eventually will again become an important coal producing area. Table 14, page 105, shows the average quality of coal from this district. o . S £ o rt fe Fulton-Peoria District This district is named from the two principal counties within its boun- daries. Mining for shipment is practically all from the No. 5 coal seam, PRODUCING DISTRICTS 51 which ranges from 4 to 5 feet thick. The coal is of medium thickness as compared with the thin coal of the Wilmington and Third Vein districts and with the thicker coals of the other districts. The room-and-pillar system of mining is employed. Cost of production is somewhat higher than in thicker coal territories, due in considerable measure to the presence of ''clay veins" or "horsebacks" which extend into or through the coal seam. (See fig. 21.) These veins are clay filling in fissures ; the clay has become hardened but not sufficiently to be designated as rock by the miner. They contribute in some measure to the ash content of mine run coal and screenings. In past years a large number of mines in this district shipped coal to Iowa and points northwest, as well as to adjacent territory, but production in the district is rapidly declining. Table 14, page 106, shows the average quality of coal from this district. Fig. 21. "Horseback" or vein of clay in No. 5 coal seam, in the Springfield District. Springfield District The No. 5 coal seam is mined in this district, which comprises parts of the counties of Logan and Menard and the northern portion of Sangamon County. The term "Springfield District" has been loosely employed, some- times being used to cover most of the territory from Fulton to Perry counties. The fact that No. 5 coal is mined in northern Sangamon County and No. 6 in the southern portion of the county is considered justification for confining the district to the area underlain by the No. 5 coal. Although the seam is the same as that mined in the Fulton-Peoria District, the quality of the coal differs in these two areas, and as they are some distance apart they are recognized as distinct districts. 52 ILLINOIS COAL The coal seam in the district is quite uniformly 6 feet thick, with good roof and favorable mining conditions. The room-and-pillar method of mining is employed. The coal seam contains the same sort of fissures found in Fulton and Peoria counties, but instead of being filled with soft clay they contain hard shale. It is too hard to contribute to dirt in the coal, but its occurrence interferes with systematic mining. Production in this district has been at approximately the same rate for many years, as illustrated by figure 13 where its output is shown in combina- tion with that from the No. 6 seam in the county. Table 14, page 105, shows the average quality of coal from this district. Grape Creek District This is a comparatively small area south of the city of Danville, in Ver- milion County. Its accessibility to market formerly enabled the district to take a prominent place in coal production. In 1897 and 1899 this county led all others in quantity of output, but in later years production has steadily de- clined. There are two commercial beds in Vermilion County that have been ten- tatively correlated with coals Nos. 6 and 7 of other parts of the Illinois field, but in the Grape Creek District the bed which is being mined is the No. 6. This seam is about 6 feet thick. Mining conditions are not of the best, as the strata over the coal do not afford a very good roof. The room-and-pillar system of mining is employed. Table 14, page 105, shows the average quality of coal from this district. Central Illinois District This district comprises the largest part of the territory in central and southwestern Illinois in which coal definitely correlated as the No. 6 is mined. The No. 6 coal is mined in the Centralia District, but this area is isolated and the quality of the coal is different enough to justify considering it as a sepa- rate district. The No. 6 seam is also mined in Williamson, Franklin, and Jefferson counties, but as these counties are separated from the Central Illi- nois District by the Duquoin anticline, and as there are differences in the quality of the coal, this area is also considered as a separate district. The coal seam in the Central Illinois District ranges from 6 to 8 feet thick; mining in most of the territory is in coal 7 feet thick. The usual over- lying stratum is a soft gray shale, unsuitable for a natural roof over mine workings and for this reason the upper part of the coal seam is commonly left in place to form the roof. It is fortunate that this extensive coal body is PRODUCING DISTRICTS 53 thick enough that a coal roof may be left, for under present market conditions the seam might not otherwise be workable. A thin "blue band" occurs in the lower portion of the coal, varying in thickness from an inch to three inches, and is separated from the coal in mining. This blue band is regarded as char- acteristic of the No. 6 seam. Mining is by the room-and-pillar method, described briefly in the section devoted to the Third Vein District. The panel system is widely employed. In this system the territory is blocked off and in mining, these blocks, or panels, Fig. 22. Plan of panel mine are protected by especially wide pillars. (See fig. 22.) In each panel are cut the usual passageways and rooms from which the coal is mined. The advant- age of the panel system is that after a panel has been worked out it may be easily cut off, usually by brick walls, from other parts of the mine, thus saving the cost of ventilation and maintenance of airways in worked-out areas. In the process of mining, the coal seam is undercut by a machine which cuts a space about four inches high and six feet back completely across the working-face (fig. 23). The support below the mass of coal to be blasted is thus removed so that the coal does not break up as much as it would if it were not relieved by the undercutting. After undercutting is done the machine is 54 ILLINOIS COAL removed from the room, and miners drill holes in the coal face and load them with explosive, ready for firing. After the miners leave the mine, which is about three o'clock in the afternoon, men especially employed to do the firing visit the rooms and light the blasts which dislodge the coal. In the morning such props are set as may be required to support the roof of the room and then the coal is loaded, as shown in figure 24, and the cars are removed by small electric locomotives which are termed gathering locomotives because they are used to gather the loaded cars from the rooms. Trolley wire is not extended into the rooms ; power is supplied to the lo- omotive when it enters the room by a cable carried on a reel mounted on the motor. The motorman in entering a room hooks the end of this power cable Fig. 23. Mining machine undercutting coal bed. By means of cutting bits carried on a link chain the coal seam is undercut for a distance of about six feet back and four inches high, the full width of the face. The cutting relieves the coal when it is shot down by explosives. The old method of undercutting the coal with a handpick was a very laborious operation. to the trolley wire in the roadway, and as the motor moves forward the cable unrolls ; as the motor moves out, the cable automatically winds up. When on haulage roads these motors get power direct from the trolley wire. On railroads switch engines gather loaded cars from factories and assem- ble them at gathering points where they are made up into trains and then hauled by road engines. The gathering locomotive, or motor, is the switch engine of the coal mine. It gathers and distributes cars from certain PRODI CING DISTRICTS 55 convenient assembly points to the various rooms in the district which it serves. The assembled trains are hauled to the shaft bottom (figs. 6a and 6b, p. 18) by larger electric locomotives (fig. 25). Upon arrival, the loaded cars are caged, clamped firmly, and hoisted to the tipple where the coal is weighed and screened for loading. Production from the Central Illinois District has maintained a compara- tively steady rate for many years. On the basis of its percentage of the State's entire output, however, it has steadily declined in recent years. Figures 13 and 14, illustrating the history of production in Sangamon County, also illus- Fig. 24. Miners loading coal in room of mine trate the status of Central Illinois District. A number of corporation-owned mines are operated in this district and they have been an important factor in maintaining the rate of production. Table 14, page 106, shows the average quality of coal from this district. Centralia District This is a small district from which an important amount of coal was formerly shipped. Production, however, has declined in recent years. The No. 6 coal is mined by the room-and-pillar method. 56 ILLINOIS COAL The thickness and mining conditions are generally the same as in the Central Illinois District. Table 14, page 105, shows the average quality of coal from this district. Franklin-Williamson District This district includes Franklin and Williamson counties and the southern half of Jefferson County, and lies east of the Duquoin anticline. (See fig. 9. p. 23). Mining began in Williamson County by slope at the outcrop about the year 1883, and reached a production of a million tons for the year 1899. In Fig. 25. Coal trains arriving at the vicinity of the bottom of the shaft. The electric locomotives are here disconnected from the train and switched off to other tracks to haul back empty cars. 1904 mining began in Franklin County, and by 1915 exceeded the output from Williamson County. Present production from Jefferson County began in 1925 when the Illinois Coal Corporation opened a mine at the town of Nason. In former years a mine was operated at Mt. Vernon, the county seat, but it is now abandoned. This old mine was located north of the thick body of coal where the seam is only 4 feet thick. Alining is in the No. 6 coal. Figure 26 shows a mine which is being operated in this general locality. The general characteristics of the seam and overlying strata are similar to those of the Central Illinois District, except that the limestone cap-rock found in southwestern Illinois is absent in a large part of Franklin-Williamson District. The most characteristic feature of the PRODUCING DISTRICTS 57 seam is the stratum of rock in the lower portion, known as the "blue band," ranging in thickness from about an inch to 3 or 4 inches, and which must be removed in mining. The seam ranges in thickness from 8 to 10 feet over the greater portion of the district and reaches the maximum thickness of 14 feet in Franklin County. The bed extends across northern Williamson and Saline counties, though it is not mined in Saline County, and it ranges in depth from nothing at the outcrop to 720 feet at Nason, in Jefferson County. Fig. 26. Surface equipment of a mine in Franklin County. Where the seam exceeds 8 feet in thickness the overlying strata are such that the upper two feet of coal is left in place to form the mine roof, as in most mines in Central Illinois District. After the rooms of a panel have been mined off an attempt is commonly made to remove the upper bench of coal which may be 2 to 6 feet thick, but the amount of coal recovered is limited both by the difficulties and by the cost. Where the cost is higher than mining in new territory there is naturally a disposition to leave much of the roof coal in place in the abandoned territory. In eastern Williamson County, however, where the seam is 5 to 6 feet thick, the overlying strata form a good natural roof so that the seam mav be mined to its full height! 58 ILLINOIS COAL From the standpoint of conservation of natural resources Franklin Coun- ty does not occupy a creditable position. In the areas of thicker coal, resour- ces may be as much as 400 per cent greater than in the 3^-foot coal area of the Third Vein District, but mining to a height of 8 feet, and with a 50 per cent recovery, the production per acre is only 30 per cent greater than in the Third Vein District. If the entire height of the coal were mined, and one half the coal left in pillars, the recovery would still be only twice that of the Third Vein District. Though the thick coal seam is wastefully extracted the largest mines in the State, and one considered the largest in the world, are located in Franklin County. The extraordinary thickness of the coal seam allows mine workings of greater height, and therefore the use of larger mine cars than are feasible in thinner seams. On each trip the larger car carries correspondingly greater quantities of coal to be hoisted to the tipple, and inasmuch as the number of hoists made in a day are approximately the same in any mine, the use of the larger mine car is an appreciable factor in increasing the rate of production. This also applies to skip hoisting. The initial development in Franklin County was made by Mr. Joseph Leiter, a well-known Chicago capitalist, who organized the Zeigler Coal Com- pany. Mining began in the southern part of the county in 1904 and disclosed a coal seam of the unusual thickness of 12 feet. The occurrence of such an ex- ceptionally thick seam attracted the attention of companies operating mines in other parts of the State and there was quite an exodus from older districts to Franklin County, resembling somewhat the rush to a new oil field. Some of the companies that followed Mr. Leiter into the field had long been engaged in the coal business, were familiar with coal users' requirements, and in plan- ning equipment gave particular attention to the preparation of the coal, espe- cially those sizes used in the domestic trade. These operators, with Mr. Leiter, took a leading position in the use of advanced methods of preparation and in developing' a market for coal thus prepared. In western Franklin County and adjacent parts of Jefferson and William- son counties, as shown in figure 43, the sulphur content is less than 1.25 per cent, so that if otherwise suitable, the coal can be used for metallurgical pur- poses and for the manufacture of water gas and retort gas. Table 14, page 107, shows the average quality of coal from] this district. Big Muddy District In this district, which lies within Jackson County, the No. 2 coal seam, 6 feet thick, occurred over much of the area. In the rest of the district the seam is separated by a rock parting into an upper and lower bed. Early mining in this district was carried on by two companies. The territory of one PRODUCING DISTRICTS 59 of these companies included part of the area where the seam was split, and when workings extended into this area mining was abandoned. Final mining- was done by other companies in the lower 4-foot bed. The coal took its name from Big Muddy River which flows nearby and down which, it is reported, the first shipment of Illinois coal was made in 1819. During the life of this field the quality of its product was generally con- sidered in the coal trade as the best Illinois coal in the market, and it usually commanded a higher price than that received for coal from other sources in the State. At one time two blast furnaces in the country used coke made in local ovens from the Big Muddy product, though the best coke used at Mur- physboro is reported to have been made from a mixture of Big Muddy and Williamson County coal. It is probable that these furnaces were the first west of Ohio River to use coke for fuel instead of charcoal. Figure 43, page 91, shows that the sulphur content of coal in this district was less than 1.25 per cent. This field was favorably located with respect to market, and production rose to a million tons per annum and then declined. The last remaining mine, in the No. 2 seam, owned by a public service corporation that produced coal for its own use, has now been worked out. The No. 6 seam occurs in the county to the northeast of the Big Muddy District and above the Big Muddy coal and the present production in Jackson County from No. 6 seam has reached a million tons per year. Saline County District Mining in the Saline County District is in the No. 5 seam instead of the No. 6 so that although the territory is a part of the Southern Illinois Field it is distinct from the Franklin-Williamson District. It has sometimes been des- ignated as the Saline-Gallatin District, though not more than two small mines have shipped coal from Gallatin County. In 1925 but one mine produced coal for shipment and it loaded only 20,276 tons. Discussion of Gallatin County and the remote Eagle Valley locality are included in Chapter II on the geol- ogy of the Illinois Coal Field, not because of importance from the standpoint of production, but for scientific reasons. Figure 5, (p. 17) shows a type of mine operating in this district, and figures 6a and 6b (p. 18) show the shaft bottom from both the loading and empty car sides. The No. 5 coal ranges in depth from nothing at the outcrop to about 800 feet at the northwest portion of the county. In thickness it varies from 8 feet to a seam too thin for mining in certain restricted areas. Mining is in coal from 5 to 6 feet thick. This coal in physical character and heat value more nearly resembles coal of the eastern fields than any other coal now being mined in Illinois. The room-and-pillar system of mining is employed. 60 ILLINOIS COAL The overlying strata are generally gray or black shale and roof conditions are excellent so that the seam is mined to its full height. The underlying stratum is fireclay or sandy shale of unusually hard character for Illinois, either of which provides a good floor in the mine workings. Saline County has produced coal in small amounts from an early period, but it was not until 1903, with the change of the Cairo Division of the Big Four Railroad to a coal-carrying railroad, that Saline County coal became available to general markets. The demand was such that production increased from about 320,000 tons in 1905 to 2,500,000 in 1908. 2 The principal buyers were users of steam coal. Beginning a few years before the World War new mines w r ere established with modern and adequate equipment for making all grades of prepared coal for domestic and other uses. At the same time a number of the older mines were considerably improved. This county, together with Franklin and Williamson counties, may be considered a new field of recent development. All the new large mines which produce commercial coal are in these three counties. Modern mines estab- lished in the Central Illinois District during the same period belong to cor- porations that are producing coal for their own use. The superior heat value of this coal and the improvement of transporta- tion facilities have been important factors in bringing about the rapid develop- ment of this district. Use of the coal has been extended successfully to gas manufacture in plants where proper purifying capacity is available. The average quality of the coal from this district is shown in Table 14, page 107. Other Coal Producing Areas In addition to the ten general trade districts there is, or has been, mining in other localities, described below. PERRY COUNTY In Perry County, lying along the crest of the Duquoin anticline, is a long, narrow, north-south area in which the No. 6 coal is of a quality intermediate between that in Franklin County and that to the west of the anticline. Several mines are worked in this area and the product sometimes competes in the market with coal from Franklin County. In former years coal was shipped from a number of small slope-mines in the exposed seams. An off-set of the line of outcrop of No. 6 coal in this area was originally interpreted as evidence of two coal beds ; the- southern was regarded as No. 6 and the northern, thought to belong above No. 6, was called No. 7. It has since been discovered that the northward shift in the line of outcrop was clue to displacement which accompanied folding along the anticline, and the con- tinuity of No. 6 coal has been established. 2 Coal Report: Dep't Mines and Minerals, p. 370, 1905; p. 91, 1908. PRODUCING DISTRICTS () 1 VERMILION COUNTY A bed 5 feet thick, known as the No. 7 seam, occurs in Vermilion County west of the city of Danville and northwest of the Grape Creek District. This coal has been mined by strip mining and small shaft or slope mines for many years. It is generally known as Danville coal and has but a limited market. ROCK ISLAND AND MERCER COUNTIES In former years an important amount of coal was produced from a long narrow area in Rock Island and Mercer counties. The coal body mined was considered to be the No. 1 seam, and the prospected area has been exhausted. There is possibility, however, of unprospected areas remaining. LIVINGSTON COUNTY Formerly coal was mined near the city of Streator, in Livingston County, in an area which also extended a little way into LaSalle County. The seam, called No. 7, was unusually thick but the roof conditions were not very good. There are a few large mounds in the territory similar to dumps from the long- wall method of mining, but here the room-and-pillar system was employed and the dumps represent the hoisted refuse from roof-falls and other sour- ces. This mining was within the area of the Third Vein District, but the No. 2 seam was never mined extensively. The one attempt made to mine No. 2 coal failed because of unfamiliarity with the requirements of longwall mining. CHRISTIAN COUNTY The deepest bituminous coal mine in the United States is located at the town of Assumption, north of the city of Pana, in Christian County. The shaft, 1020 feet deep, reaches what is considered the No. 1 coal seam. Until recently that seam has been mined together with one considered the No. 2 seam. Production has never been large but the output for many years com- manded an excellent market. MOULTRIE COUNTY At the town of Lovington, in Moultrie County, a shaft reaches a coal body about 8 feet thick, considered the No. 6 seam, at a depth of 904 feet. This mine was formerly important but is not now operated. MCLEAN COUNTY At Bloomington, in McLean County, there is a deep shaft 3 in which the No. 2 seam is now mined, though formerly both No. 5 and No. 2 seams were This mine was abandoned in 1929. 62 ILLINOIS COAL worked. This is the largest mine in the State that produces coal for local consumption. None of the coal is shipped, and practically all of it is marketed in the city. MACON COUNTY At Decatur, in Macon County, there are two important shaft mines in coal No. 5 that supply a portion of the local demand. 4 HENRY COUNTY At Alpha, in Henry County, there is a shaft to Coal No. 1 from which a considerable amount of coal is shipped. GRUNDY COUNTY At Verona, in Grundy County, a new shaft reaches a body of coal about 10 feet thick, thought to be No. 7. About 2,000,000 tons of coal have been shipped from this mine since it opened in 1924. 5 4 One of these mines was abandoned since 1929. 5 This mine was worked out and abandoned in 1930. CHAPTER V— COAL MINING IN ILLINOIS Mine Openings With a few exceptions which apply mostly to strip mines, all mines now shipping coal by rail are reached by vertical shafts, but the first mining in Illi- nois was along outcrops, and the coal was reached by inclined slopes. The early developments were in localities where coal seams sufficiently thick for mining were exposed at the surface. Such localities are indicated below. Seam No. 1 — Rock Island County, on the bank of Rock River. Seam No. 2 — Grundy, Will, and LaSalle counties ; in a number of the western counties (mined for local market) ; and Jack- son County, on the bank of Big Muddy River. Seam No. 5 — Fulton, Peoria, Saline, and Gallatin counties. Seam No. 6 — St. Clair, Williamson, and Perry counties. In the last county, because of irregularities caused by the Duquoin anticline, two beds were thought to occur and No. 6 coal was in some places called No. 6 and in other places No. 7. Seam No. 7 — Vermilion County, on branches of Vermilion River. There are a large number of very small slopes and drifts in the western counties in various seams, and a few occur in some of the interior counties where there is a small production for local use. The early shipping mines were adjacent to river transportation, but these were largely abandoned at an early date for operations located along railroads. Depths of Shafts Depths to the different seams at shafts vary as follows, though some of the mines for which figures are given are no longer operated. Coal No. 1, or the seam so designated, ranges from an outcrop in Rock Island to a depth of 1020 feet in a mine at Assumption in Christian County. Coal No. 2, in Grundy, Will, and Kankakee counties, has been mined in shafts ranging in depth to 200 feet. In the Third Vein (LaSalle) field the depths of shafts range from 300 to 465 feet, depending on the surface eleva- tion. Coal No. 5, mined by shafts in Fulton and Peoria counties, varies in depth to 196 feet. In the Springfield district, counties of Sangamon, Menard, and Logan, shafts are as deep as 250 feet ; present mining is practically all at 63 64 ILLINOIS COAL o pj i_i ii, NO .2 o Ph + 3 -a o u ft . no t^ 0) > CM CM ^f CM r-H (J << *0 o ON LO rH CO t^ o ^ Ih 00 NO CM to CO 00 -t- 3- Ph O on ON rH o" t-T r^ co^ NO" co" OO "* cm" co" rH CO rH > o o H U U f^Jw " £ J O -^ cS NO 1 ON w m < Ih e c ON On +^ NO <0 to Ph aj + + + y Oh >. T3 *0 LO CM ON to CO ON LT CO oo C >h to co to c 00 Tf rH NO o to r^. NO H CM CO CO Ih 8 r^ on t^ c CM h ^ Ih H, tfl u 3 "o C be ON ON ON CO co CO £ < OO i — i i — i O o on r^ ON « r^ co NO Ph o rH rt" + + + Ih Oh lO t^s CO to OO NC CM ON NO O CM On o .s 00 ^ oc £ ,-H ^H Tt- c 00 o NO ON LO o O0 T ^ LO H O c^ ON r^ ^r NO Ih a; e LO rH rH CM to Ph + + + C ^-j MH . LO CM NC ^ o CM NO C oo a H hO c " i— u eg o o ^ w t- H COAL MINING 65 about that depth. In Saline County the depth varies from short shafts near the outcrop to 600 feet at Galatia in the northern part of the county. Coal No. 6 is reached by shafts ranging from shallow depths to 722 feet at Pana in Christian County, 904 feet at Lovington in Moultrie County, and 725 feet at Nason in Jefferson County. Formerly a shaft at Mt. Vernon reached the coal at 860 feet. Coal No. 7 has been worked at depths of from 15 to 208 feet, depending on the surface elevation. Mine Data Tables 9a and 9b present data for the year 1925, to which, for the pur- pose of comparison, corresponding figures for 1908 are presented as applying to the period covered by the former bulletin on the Illinois Coal Field. 1 INTERPRETATION OF MINE DATA The table shows three outstanding features : a decreased number of mines using the longwall method of mining ; an increased mine production ; and an increased number of mines operated by industrial or public service corpora- tions producing their own coal. The decrease in the number of mines using the longwall method of min- ing is due to inability to meet the competition of better coal produced at a lower cost. In general, production per mine in 1925 had doubled that of 1908. The new Orient No. 2 mine, of the Chicago, Wilmington, and Franklin Coal Com- pany, shown in figure 2, promises to surpass any single 1925 record. This mine has an elevating capacity of some 13 tons per hoist, which, at 1000 hoists per day would give a daily capacity of 13,000' tons. Assuming 240 working days in a year as a possible maximum, this would give a production of 3,120,000 tons, doubling the high record of 1925. Of the nine mines producing more than a million tons each in the year 1925, five are located in the Central Illinois district and are operated by corporations producing their own coal ; the other four are in the southern Illinois coal field. Many of these large mines have not only large production capacities, but their holdings insure long lives. Prior to 1908 production of coal by corporations was carried on by only a few railroads and by three zinc industries. During the war, however, when supplies were so uncertain, a number of other corporations purchased existing* mines and opened new ones. Some of these corporations use coal in the form of screenings in stoker-fired furnaces, but unless the large coal can be sold in the market it is necessary to crush mine run, a more expensive fuel than Illinois State Geol. Survey Bull. 16, 1910. 66 ILLINOIS COAL screenings. The crushing of mine run was economically justified during the war but thereafter the small demand for the larger coal made it necessary to crush mine run coal as a regular procedure. Such corporations have found their fuel cost much higher than it would have been had they been able to take advantage of the commercial fine-coal market. Coal Stripping The first coal stripping of any importance in Illinois was begun many years ago in Vermilion County, where on the branches of Vermilion River the No. 7 seam was overlain by thin cover. The original site of operation was known as the Mission field. Since that time stripping has been carried on more or less continuously at different locations in this territory. The view shown in figure 27 is of a recent stripping operation in the Middle Fork of Vermilion River Valley. Within the last five years a number of stripping projects have been in operation in southern Illinois along the line of outcrop of coal seams Nos. 5 and 6, in Fulton County near Cuba in the No. 5 seam, and recently in Grundy County, west of the town of Wilmington, in the No. 2 seam. 2 Table 10 shows the counties in which coal is mined by this method, the seams stripped, the quantity and the percentage of the county output pro- duced bv this method in 1930. Table 10. — Production of coal by stripping in 1930 a County No. of strip mines Coal seam stripped Tons produced Total By strip Per cent by strip Fulton . . . Henry Jackson . . Livingston Perry .... Saline St. Clair . Vermilion Will Williamson State 2 No. 5 1,634,772 885,249 54.1 1 No. 2 504,761 397,510 78.7 2 No. 6 2,054,836 805,337 39.2 1 No. 7 24,351 1,223 5.0 4 No. 6 3,309,648 2,251,321 68.0 2 No. 5 3,670,144 192,365 5.2 1 No. 6 2,447,784 275,320 11.2 2 No. 7 2,930,924 420,441 14.3 1 No. 2 865,666 865,666 100 10 Nos. 5, 6 ' 4,107,573 181,535 4.4 26 54,035,116 6,275,967 11.6 a Compiled from Forty-ninth Coal Report of Illinois, 1930: Department of Mines and Minerals, 1931. 2 Since 1929 a large strip mine has been operated near Atkinson in Henry County. COAL MINING 67 Fig. 27. Airplane view of a recent stripping operation along the Middle Fork of Vermilion River Valley, Vermilion County. Fig. 28. A modern electric shovel used in coal stripping. The boom is 90 feet long and the bucket has a capacity of 8 cubic yards. Note the comparative size of the men. 68 ILLINOIS COAL p is ' J^^BllBt I "*^S 1 3 II^ V ■ §1 ■ L S 1 < jy Si ■ flf * .11 iMn • If '• $3l m * ^m V ^K ■^^w : ill ral 'v** . HH COAL MINING 69 The apparent simplicity of the coal stripping operation is an incentive that often governs those who develop such property. The cost of the plant ready to produce coal is less than that of a shaft mine. The stripping method involves more mechanization and less lahor than the shaft method. Figure 28 illustrates the remarkable development of the electric shovel brought about by the stripping method. Furthermore, under favorable conditions, the cost of producing a ton of coal may be less than in shaft mining. On the other hand the life of the stripping mine is much shorter than that of a shaft mine, for the area stripped is necessarily limited by the amount of cover. Because the stripping plant has a shorter life this method may in the end prove the more expensive. Experienced supervision, not always to be had, is imperative in order to meet the inevitable hazards from wet spells and consequent slides of spoil banks back into the workings. The re-handling of this material is apt to prove expensive. Drainage of the pit is always a somewhat serious prob- lem and so is the recovery of the coal without including dirt that would reduce its quality. In order to meet the competition of coal from shaft mining, modern tip- ples, like that shown in figure 29, must be constructed and the coal adequately prepared. As underground mining in localities near the outcrop approached terri- tory in which the cover over the coal was too thin to provide a suitable roof, mining ceased, and from the standpoint of underground mining such coal was abandoned and appeared as so much coal lost. In such places strip mining gives a more complete recovery of the coal. In stripping coal the ground for a time is ruined (fig. 27). The damage to the land may be of little consequence in locations where the surface has no value for agricultural purposes, as for example, in Vermilion County, on branches of Vermilion River. In other localities, however, where land is agri- culturally valuable, stripping may not be a conservative measure. Once the coal is removed the land is of no further value, for at least a considerable length of time, and then only after expensive leveling and perhaps soil treat- ment. CHAPTER VI— PREPARED COAL Introduction Although operators attempt to produce a greater proportion of large- sized and a smaller proportion of fine coal, at best the coal as hoisted consists of a great variety of sizes and a more or less definite quantity of each size. There are now nine standard sizes produced as shown in Table 1 1 . Table 11. — Standard sizes of coal Item, Trade name Dimensions in indies 1 Lump 6 and over 2 Furnace 6 by 3 3 Small Egg 3 by 2 4 Stove or No. 2 Nut 2 by 1% 5 Chestnut or No. 3 Nut iy 4 by y 4 6 Pea or No. 4 Nut 3 A by H 7 Carbon or No. 5 Nut Y% and less 8 2-inch Screenings 2 and less 9 1% -inch Screenings 1% and less Lump and No. 2 nut coal are shown in figures 30a and 30b respectively, Preparation of Coal at the Mine development of present methods of preparation During the early period of Illinois production there was practically no market for fine coal such as screenings, hence as much large-sized coal was produced as possible. In mining, the seam was undercut by hand-pick to facilitate its removal with minimum breakage, but the undercutting produced a quantity of small sizes and there was some breakage of the large coal. Fine coal from these two sources, without value, was hoisted with the large size and was removed by screening. The screens were simple, consisting of iron bars set at a rather sharp angle a little distance apart, and the coal moved over the screen by gravity to> the railway car. The salable product was lump coal that passed over the 1^2 to 2-inch screen, depending on the space between the bars, and the miner was paid only for the amount of screened coal he pro- duced. The introduction of mechanical stokers for power boilers furnished a market for small coal, for these furnaces could not use the larger size. At first screenings could be obtained in some places merely by paying the freight and this was considered a cheap way of solving the problem of disposal at the 70 PREPARED COAL 71 P » -^ 1 WW'-'-*>&^^^r -. r ^~1 ■ ■: * O. - - - 'W mfk 'Jr' ; ^ : ' 1 - > \ «:'M • 1 *'^£^ ■§ f 1 ^ ''■'."'"' • VI .v -rl ^ -.,!*- ^ ^Hk * v r,v>- & «, \l*'i * : -' ~ "w^ . ■, £ jj| - -, f ;*'-i% •'#<% -\. .4"^ ; §p . , * .-.,— ' '"*■' W «^H r w. ; ,'| ^8 3; •^ : ;.:> ; « '% . \ > Fig. 30a. Lump coal, including that which is retained on a 6-inch screen. 1 - "**t^H HBl* e >sMHP?.^^^-?*i ***** c j pw»» •wfpr. v ^ ; *^ -" "„ "' j " s\ s. < * v. % &38 «J ' "' '■■§ :f , . 1 iV*ft< r 5 '.1 ' #9 KVSaC Fig. 30b. No. 2 nut coal — that which passes a 2-inch screen and is retained on a 1^4-inch screen. 72 ILLINOIS COAL mine. Later a few cents per ton covered the mine price. As the use of stoker furnaces increased, the market for screenings increased, as well as the price. The result was a change in payment from a screened-coal basis to a mine-run basis and, as payment was the same for small and large coal, the incentive to produce large coal ceased to influence the method of mining. 100 90 80 70 60 50 40 30 20 10 ! S L N f \ / S \ / > i \ i \ \ / \ l s — — 1882 84 86 88 90 92 94 96 98 1900 02 04 06 YEARS 08 Fig. 31. Percentage of total State production reported as lump coal from 1882 to 1910. The drop in the curve after 1899 reflects the change from a screened-coal to a mine-run basis of payment. (From data in reports of the Department of Alines and Minerals.) Figure 31, showing the percentage of lump coal produced, is plotted from reports of the Illinois Department of Mines and Minerals and covers this period of transition. Prior to the year 1896 the coal reported as "lump" was coal over the screen, a mixture of sizes. At the present time, the term "lump" refers to all sizes of coal passing over a screen having round holes 6 inches in diameter. During the period of the screened-coal basis of payment the miner used a minimum amount of powder in blasting out the coal but with the change to the mine-run basis of payment the use of explosives increased great- PREPARED COAL 73 lv, as shown in figure 32. This diagram explains in part the condition illustrated in figure 31. This change in mining led to over-production of fine coal. There was a rapid growth in the number and size of stoker-fired furnaces, but not enough to absorb the screening production. Although the demand became sufficient to command a gradually increasing price it has never been high enough, under normal conditions, to equal their cost. Screenings, therefore, sell for less than the cost of production, and this of course has resulted in the maintenance 1 ^ t i » < t i > < i ," > i i X s « / < t / r> / / / / | / / / ) 1 ' ( h 1 1895 96 97 98 99 1900 01 02 03 04 05 06 07 08 09 YEARS Fig. 32. Average curve showing increase in the use of powder per ton of coal to blast out coal after the change from a screened-coal to a mine-run basis of payment. (From data in reports of the Department of Mines and Minerals.) of a price for the larger sizes high enough to cover the loss occasioned in marketing the screenings. The use of stoker-fired furnaces has grown so rapidly that if there had not been increased efficiency in the use of coal the demand for screenings at the present time would probably be greater than the supply, with the result that the price for this coal would be equal to that of mine run. In 1900 the amount of coal required to generate a kilowatt hour, in the best electric plant using Illinois coal, was 5.2 pounds. At the present time it is about 1.5 pounds. Increased economy in general service has been proportional. 74 ILLINOIS COAL In addition to the demand for stoker fuel a growing demand for mine run coal came to absorb a considerable portion of the small-sized coal. After 1899, when due to the mine-run basis of payment a portion of the cost of pro- ducing screenings had to be assessed against the screened coal, many coal users began to buy mine run coal because of the lower price. The demand for mine run, of course, decreased the production of screenings. The market for mine run coal has, however, in turn declined in a marked degree in more recent years as' the user has learned the advantage of prepared coal over mine run. In response to the demand for the prepared coal operators have enlarged their screening plants to produce a variety of sizes. Fig. 33. Shaker screens used in making prepared sizes of coal. Preparation Equipment The making of these standard sizes requires elaborate screening equip- ment and tipple plants. The coal is discharged from the weigh hopper to the screen having the smallest openings, then to successive screens having increas- ingly larger openings. The first screen, having 1^4 -inch holes, makes 1%.- inch screenings, which are either discharged directly to the railroad car and shipped as such, or conveyed to the re-screener to be separated into the small prepared sizes. The remaining coal passes to the 2-inch screen, which makes coal 2 by 1 34 inches; then to the 3-inch screen, which produces coal 3 by 2 inches, from which it passes to the 6-inch screen (fig. 33), which makes coal 6 by 3 inches. The coal that passes over this screen is called 6-inch lump and PREPARED COAL 75 is in size 6 inches or larger. The photograph shows these screens one below the other, set at a slope to facilitate the movement of the coal, which is accel- erated by a vibratory motion. These are usually referred to as "shaker screens". Coal 3 by 2 inches, 6 by 3 inches, and lump, pass from the screen to the picking tables (fig. 34), at which men are employed to pick out of the moving coal such foreign matter as the miner failed to remove when he loaded the coal into the pit cars in the mine. The coal 2 by \% inches, or 2 by V/ 2 inches, depending on the size adopted in preparation, passes from the screen to the loading conveyor, but M I mflflBMni ^2ta . fc^tt W fa JJHpp^ 'hrtHfeB JM ■-: ~ibk~ jsmm * • ■*.<•• m _,- c ' • l n iff! / Fig. 34. Picking tables at which men are stationed to pick out foreign matter from the moving coal. This stage is intermediate between grading and loading on railway cars. (This applies only to coal over two inches in diameter.) is not hand picked. Screenings go direct to the railway car, for it is not necessary or feasible to pick these small sizes. If certain sizes are to be eliminated such screen plates are blanketed over. In this connection one of the recent developments in tipple design is a cross conveyor that allows dif- ferent sizes to' be put back together again. Buyers of a definite size of coal demand that it reach them with a mini- mum amount of breakage. This requires careful handling and additional equipment in the tipple, particularly in the loading of sizes over two inches. When the coal is broken down in the mine by the explosives some of the pieces become shattered or are cracked so that they fall apart in passing over the screen. Such broken coal passes through the screen to the next smaller size, but to make sure that all of it is removed the 6-, 3-, and 2-inch main 76 ILLINOIS COAL ^gj^' ^pPB 11 ^^^ ^»T^ jB^HHe^, *^» 1 yy. 1 1. f !: **•- i.vj '<:■ >-*.-^ ; up v _..;.. .'..:.; ,■■■ ' , j . ■ n \W i-j^^'--H, -Uj f^-,^S *M '••'■-■■ • ■■■. s ;.: ,,- '.^/! ■•""1 \ ". •> . -V:.;. S'i. ■;. _"-^ » *•--»! HP ' •' :^ — ■ • ^"-J* >v. -I "' W_ ." •• •"*'* . ' II 1 i; | If \ Fig. 35. Adjustable loading conveyors that carry the coal from the picking tables to the railway cars. Fig. 36. A battery of screens for separation of small coal into prepared sizes. These screens are given a rapid vibratory motion, and they discharge directly to a conveyor belt. The coal that goes through the screens is conducted to other screens where a still smaller size is made. PREPARED COAL 77 screens are provided with supplemental screens and in effect these sizes are double-screened. After the coal leaves the screens and the picking table it passes to a moving conveyor (fig. 35) for loading in railway cars. The end of this conveyor, which reaches the car, is so arranged that it may be readily raised or lowered and the coal is placed without falling as the car is gradu- ally moved while being filled. PREPARATION OF SMALL SIZES Small coal, or screenings, is following the same market trend as mine run, and such coal is separated by a battery of screens (fig. 36) into small prepared sizes as shown by items 4, 5, and 6 of Table 11, just as coal over two inches is separated into large sizes. The preparation of these small sizes began in Williamson County. The first mine plants and methods were crude, as compared with present practise, but they were quite advanced for that time. Williamson County operators early adopted the coal washing process for the purpose of lowering the ash content by reducing the foreign matter in screenings. It so happened that in the wash- ing process adopted the coal was first separated into sizes as items 4, 5, 6, and 7 (Table 11), and each size was washed separately. Having separated the coal the mine operator did not entail the expense of reassembling the sizes but sold them separately, giving each a distinctive trade name, as Nos. 2, 3, 4, and 5. In that day, 3 by 2 inch coal was called No. 1 nut, as the leader of the numerical order, but was not washed. The washed sizes were then known as Carterville washed coal, from the original shipping point, and became very popular, not because of their uniformity but on account of being washed. In 1904, production began in Franklin County from the same No. 6 coal seam mined in Williamson County, and soon the same preparation was made by separating the screenings but without washing. It became apparent that the value was due to the sizing rather than the washing of the coal and lead- ership in the making of these sizes passed from Williamson to Franklin County. The localities now leading in production of the small prepared sizes are the counties of Franklin, Saline, Williamson and Madison. Coal washing has declined, but the demand for the unwashed small preparation is growing rap- idly. Experience has shown that its value lies in uniformity of size and that it is more satisfactory to keep the coal clean by careful mining than to wash out the dirt. As a result of the preparation of these small sizes, carbon, }i inch and less in size, has little value now as a stoker or hand-fired furnace fuel. It has, however, a special market with certain industries that burn coal in the form of powder for it requires but a minimum amount of grinding. This market 7* ILLINOIS COAL is growing because of the increasing use of pulverized coal as a steam-making fuel. Formerly coal-washing plants were common at mine shafts, especially at those working the No. 6 coal seam. Washing was carried on most extensively in Williamson, Madison, and Macoupin counties; in the first county the practice has declined to a marked extent, but in the last two it is still con- tinued on much its former scale (fig. 37). In the Third Vein (LaSalle) District, where the longwall method of min- ing: is employed, the seam is undercut by hand-pick in the fireclay below the Fig. 37. A coal mine tipple and washery at Staunton, Illinois. The washery is located to the left of the tipple. coal. This is done to remove the support from below the coal in order that the pressure from above will break it down. As a result, a considerable quan- tity of fireclay becomes mixed with the fine coal, and this fine coal must be washed to make it salable. It is sold generally in the form of \%. -inch screen- ings. This method was also practised in the Wilmington District though min- ing has been discontinued in that area. The production of fine coal, however, is not large, because the amount of breakage in this system of mining is small, and only a limited proportion of the output requires treatment. Some coal was washed in the Grape Creek District to remove dirt due to unfavorable roof conditions. Coal washing has been confined entirely to the product from seams Nos. 2, 6, and 7. PREPARED COAL 79 Prior to the time the small prepared sizes were made by the dry process these washed sizes commanded a market because they were washed and not because of preparation, or sizing. When it was realized that the increased value was due to sizing instead of washing the washed product could not com- pete with the dry prepared coal, except in districts employing the longwall method of mining, because of the overhead expense, the cost of maintenance of the plant, and the loss of fine coal. One of the special difficulties met with in marketing washed coal is that in cold weather it freezes as it is loaded and makes unloading difficult and expensive. MARKETING OF PREPARED COAL It is apparent that with a demand for nine sizes the coal producer must seek the users of the different sizes. This involves a higher cost of selling, and the preparation of the sizes requires more expensive equipment than if all customers were satisfied with mine run. Although for a time operators placed some emphasis in their sales depart- ments on selling a combination of prepared sizes, it has worked out that users of coal generally prefer only one of these sizes. Only occasionally do the larger operators receive orders for mixed sizes, or mine run, other than for railroad fuel. Use of Prepared Coal small-size coal as stoker fuel Although the market for small prepared sizes is growing, their value, especially for stoker fuel, is not well understood. The reason is in part his- torical. When mechanical stoker furnaces were first introduced the only fuel that could be used was screenings, available at a low price. At that time the advantage of a stoker-fired furnace over the hand-fired furnace as an econom- ical and convenient investment was not sufficiently appreciated to justify the higher cost of installation. The difference in the price of coal used in the stoker-fired furnace as compared to that used in the hand-fired furnace was, however, readily apparent, and this stimulated the installation of stokers. The original low price no longer prevails and the small prepared sizes are taking the place of screenings as a more economical fuel. At the present time for points in Iowa, Minnesota, and Wisconsin the freight rates for coal 2 inches and less in size are 17 to 36 cents per ton below the rates for larger coal. This rate system has become known as a "screen- ings rate" and for this reason users' attention has been centered on screenings. They have not always realized that these rates also apply to shipments of small prepared sizes of coal. 80 ILLINOIS COAL RESEARCH IN THE USE OF SMALL SIZES One of the difficulties in understanding the superiority of small prepared sizes over screenings has been the fact that the B. t. u. of small prepared coal is only from 2 to 4 per cent greater than that of screenings. It is quite nat- ural that, in the absence of more comprehensive data, the B. t. u. was form- erly considered the chief basis for comparison. (See pp. 92, 97-98.) However, the problem has been studied by various coal consumers in research experiments on steam production in chain-grate stokers 1 with results < > o o > °< > < ) o o o 0( y V o°" > s ( » > c > f ,/ Vo 1 s N 5 fc < v t 1 1 > o X < ) o < 'o u o o ; o < > < o Ph o o o o o w < 1 f 1 o o / o .ZO .30 .40 .50 AVERAGE SIZE OF COAL IN INCHES .60 Fig. 38a. Curve showing the behavior of coal screenings in efficiency of steam produc- tion. (After Abbott, W. L., Some characteristics of coal as affecting performance with steam boilers : Journal Western Society of Engineers, vol. 11, 1906.) Figures that have prompted a growing demand for the small prepared coal. 38a and 38b are based on some sixty tests of l.^-inch screenings, made under the same conditions. The screenings were fed to the chain-grate stoker hop- per from an overhead bunker. As shown, horsepower and efficiency of com- bustion were influenced by the size of the coal. 1 Abbott, W. L., Some characteristics of coal as affecting performance with steam boilers: Jour. Western Soc. Engineers, vol. 11, p. 534 ff., 1906. PREPARED COAL 81 The screenings used in these tests all analyzed about the same, the B. t. u. not varying more than 3 per cent. The differences in performance, on the basis of efficiency, ranged up to 70 per cent, and capacity differences ranged up to 400 per cent. Some of the* highest B. t. u. coal gave poor results, and some of the lowest B. t. u. coal gave excellent results. These screenings were all from one locality, and the tests did not: really consist of trial of dif- ferent coals, but rather were continued tests of the same coal. Differences in performance were due principally to the degree of bunker separation. 1 1000 800 ° 1 o o o \o ( 1 o ( ) w 600 c 0/ ) o o o / / < ) f o y*i » < > o c > o < » u ( > to ) ( ) § 400 < I < > u < ) o o / £00 / / o 1 .20 .30 .40 AVERAGE SIZE OF COAL IN INCHES .50 .60 Fig. 38b. Curve showing the behavior of coal screenings in capacity in steam production. (After Abbott, W. L., Some characteristics of coal as affecting performance with steam boilers: Journal Western Society of Engineers, vol. 11, 1906.) REASONS FOR THE RANGE IN PERFORMANCE OF SMALL SIZES The diagrams show that when the coal used was of small diameter, or contained a large quantity of "duff" or of very small pieces, performance was poor ; as larger coal was used the performance became better until the average diameter was 0.29 inch and this gave the best result. With slightly larger coal the performance dropped, to rise again as the coal became still larger. 82 ILLINOIS COAL The chief reason for the range in performance is the difference in the condition of the fuel bed. When fine coal predominates the fuel bed is too dense, and the result is that air does not penetrate properly, causing the coal to burn slowly and produce less heat. After the volatile matter had been driven off the coal tends to cake and become coke. The coke forms in masses which burn through in places and allow excess air to flow through the fuel bed. T 1 •X / -,*?? -$£ &J7 ^£? v>> x ? y £ ,/ -**£-*■ ^<*$^" +3&>~ s' s' — -^ 9 i ^®s^ 3. - *&£'-' „ ®&%i v&g?Jz~~ 1 **<* 1. 1 15 20. ?-5. 30- PER CENT OF OVER-SIZE PIECES 35. Fig. 39. Relation between over-size of coal in screenings and ash-pit loss of un-burned coal as determined by tests with chain-grate stoker. (After Duennes, F. C, Fuel preparation for chain-grate stokers: Power, vol. 62, No. 21, 1925.) When the large size of coal predominates in the screenings the fuel bed is too porous and allows excess air to flow through. The air supply may be so excessive at the front of the grate as to prevent temperatures high enough to ignite the coal. This so reduces the capacity that steam pressure falls and the plant may not be able to carry the load. PREPARED COAL 83 It an ideal mixture of sizes could be obtained, the value of screenings as a fuel would be relatively high, but uniformity of mixture with proper pro- portion of suitable sizes cannot be obtained. Even if uniformity of mixture could be assured at the mine, it would be destroyed by separation in bunkers and bins. An illustration of how separation occurs may be taken from a plant at which screenings were unloaded through windows onto the floor in front of 1 | zriz i 80. i 1 ! ! ! 1 ■ 1 ! i_ 75. 1 i : ' "^ < JH E 51 U N U" r - 1 i ! so would require running short fires, and the excess air entering the furnace through the back end of the grate would cause greater loss from this source than the gain due to completely burning the coal. If the pieces of coal were the same size they would all burn at a uniform rate, and so arrive at the end of the grate uni- formly consumed. COMPARATIVE PERFORMANCE OF SCREENINGS AND SMALL PREPARED SIZES Figures 40a and 40b show the comparative performances of screenings and small prepared sizes of coal with reference to efficiency of combustion and capacity secured in steam production. From the standpoint of fuel economy the small prepared sizes of coal are not subject to the variable characteristics of screenings. They afford a fuel bed sufficiently porous to insure proper air penetration, and when the fire- thickness is suited to the size of coal excess air is avoided. The fuel bed is in condition to take sufficient air for good combustion, but not so much air as to cause loss of heat. The small sizes not only burn uniformly and freely, but with the same strength of draft they burn much faster than do screenings. It is for these reasons that the uniform preparation gives a more satisfactory performance than screenings. CHAPTER VII— ANALYSES OF COAL Origin and Physical Character of Coal From peat beds of enormous extent and great thickness which existed in the Illinois coal basin during Pennsylvanian times have come our present coal beds. These peat beds were made up of partly decomposed portions of trees and undergrowth which grew in luxuriant profusion in the forest swamps of the period. The change from peat to coal is believed to be due to pressure of overriding sediments beneath which the peat became buried, to other earth pressures, which in parts of the coal basin produced folding and faulting of the rocks, and to a less degree to heat from the interior of the earth. As these influences made themselves felt the peat was gradually changed to lignite, then to sub-bituminous coal, and finally into bituminous coal within which rank it is now classified. The physical components of bituminous coal are readily discernible. Within any piece of Illinois coal one can generally recognize three differently appearing layers or bands. These are the bright or glance coal, the dull coal, and the mineral charcoal, the last having the characteristic appearance which suggests its name. The glance coal is composed of woody material which was incorporated into the peat swamp, and the dull coal is composed of var- ious sorts of plant materials, crushed wood fragments, pollen, resin, seed cases and other more resistant parts of plants. Some doubt exists as to the origin of the mineral charcoal. It is thought by some investigators actually to repre- sent charcoal resulting from forest fires, by others it is regarded as the effect of oxidation of the surface of the peat during periods of exposure. It is pos- sible that more than one cause was operative in its formation. Chemical Character of Coal coal analyses Curiously enough, although chemical analysis of coal is a matter of great interest, it has not until recently occupied much of the attention of chemists, and even yet very little is known about the chemical nature of the substances occurring in coal. PROXIMATE ANALYSES What then are the coal analyses which are so commonly presented as evidence of the character of coal? Those known as proximate analyses 86 ANALYSES OF COAL $7 have been worked out by the industrial chemist and industrial user of coal to reveal the behavior of the coal in combustion. The commercial user is interested in the proportion of non-combustible and combustile ingredients in coal. The most important non-combustible substances are moisture and ash, and the relative proportion of each is of interest. The combustible por- tion consists of volatile matter, which may become smoke producing, and fixed carbon which is not smoke producing. There is also interest in regard to the actual heating value of the coal. In English speaking countries the calorific value is generally given in terms of British thermal units, commonly abbre- viated to B. t. u. — one B. t. u. being the heat required to raise the temperature of one pound of water one degree Fahrenheit. A proximate analysis of a sample of coal, therefore, states the amount of ash, moisture, volatile matter, fixed carbon, and B. t. u. The amount of sulphur present is also commonly included. METHODS USED IN OBTAINING THE CHEMICAL DATA ON ILLINOIS COAL Many proximate analyses have been made of Illinois coal from samples carefully collected according to standard practise from the face of the coal seam. In no case were the samples taken from cars. A total of 858 samples were collected from 242 mines, analyzed, and the results assembled in the forms shown in Tables 13 and 14. The analytical work was done in part by the United States Bureau of Mines and in part by the Department of Indus- trial Chemistry of the University of Illinois. MOISTURE IN COAL By referring to Tables 13 and 14, pages 99-107, information may be ob- tained as to the various substances in the coal, the former table giving the data by counties and the latter by trade districts. The moisture content shown in these tables is that moisture which is released by the coal when heated under specified conditions for one hour at 221° Fahrenheit (105° Centigrade). It is well to bear in mind that the data given are for samples obtained from the face of the coal seam in the mine, and that the moisture content of coal in the seam is fairly uniform for a considerable area, and for as much as a county. Changes in moisture content during shipment cause much con- fusion, trouble and controversy, because it is not always understood that coal is purchased as loaded and weighed at the mine. Where domestic users are buying coal after it has been for some time on cars or in dealers' yards, pur- chases in hot, dry weather have the advantage of being better from the stand- point of lower moisture content and higher B. t. u. per ton than purchases in cold, wet weather, these advantages being in addition to the usual lower sum- mer price. ILLINOIS COAL ASH Ash in coal as loaded for shipment is a variable quantity. It is the one ingredient of coal represented in the proximate analysis over which the min- ing companies exercise control. The possible ash substance which appears in the coal shipment is derived from three sources : ( 1 ) from the coal substance itself; (2) from impurities in the coal seam; and (3) as dirt and rock from roof or floor which may become mixed with the coal in process of mining. Ash of the first variety is the inherent ash which represents the ash in the woody substances from which the coal is composed. Over the quantity of this ash the producer has no control. The quantity of the second and third ttOO 700 600 • 3 ^ T- X N . >— *% -. . o 500 • \ *» \ ► \ 400 n \ o • \ \ \ h \ \ \ •\ V \ V \ ' J \ \ \ ,\ A\ c .• \ • • HORSEPOWER EFFICIENCY • -0 i V • AVERAGE VALUE 1 o z o 3 o 50 PER CENT OF ASH IN DRY COAL Fig. 41. Relation between the per cent of ash in dry coal and the efficiency and horsepower developed during tests. (After Abbott, W. L., Some characteristics of coal as affecting performance with steam boilers : Journal Western Society of Engineers, vol. 11, 1906.) varieties of ash are under his control, for by care in mining and preparation the amount of this ash shipped in the coal may be kept at a minimum. The importance of careful preparation and the resulting reduction in the ash con- tent of the prepared coal rests partly on the fact that carefully prepared coal has higher heat value than poorly prepared coal, because of the greater pro- portion of heat producing material in the shipment. The analyses which show the composition of coal on a dry basis (Table No. 13, pps. 99-104, condition 2, see any county) show the ash content on a ANALYSES OF COAL 89 better comparative basis than do analyses in which moisture is included (con- dition 1 of same table). This is because in its combustion coal loses moisture by evaporation, leaving coal and ash, and the proportion of ash in the dry coal determines the amount of heat to be expected in combustion. For ex- ample moisture and ash are each 10 per cent, this moisture is expelled by the heat of the fire ; therefore the ash that interferes with combustion instead of 10 per cent is 11 per cent of the coal burned. If moisture is 15 per cent and ash is still 10 per cent, then the ash that interferes with combustion is 12 per cent. The use of the dry coal analysis as a means of comparing the relative proportions of ash and coal substances is the only instance of its legitimate and useful application. Figure 41 shows the relation between the H 300O ^ l H Z900 £ W « 2600 < F*H 2700 in w 2600 rt w 2500 I 2400 w < 2300 o w 2200 rt £ fH 2100 < £1 zooo <. 1900 K c 1800 1 , • • • . a • • < • * • 3' 4 5 (o PER CENT OF SULPHUR IN COAL Fig. 42. Relation between the sulphur content of coal and the fusion tempera- ture of the ash. (After Langtry, W. D., The fusion temperature of coal : Power, vol. 67, p. 192, 1928.) per cent of ash in dry coal and the efficiency and horsepower obtained in combustion. The melting temperature of ash varies for different coals, but on the whole the melting temperature of ash of Illinois coal occupies a relatively low position with respect to that of coal of other fields. To the commercial consumer sulphur has long been thought of import- ance in its effect upon the melting point of ash, it being thought that the high- sulphur coals are commonly those the ash of which has a tendency to melt and 90 ILLINOIS COAL clinker in the tire. However, high-sulphur coal may or may not be accom- panied by ash with a low fusion point, and not all easily fusible ash is found in high-sulphur coal. In tests of coal having a sulphur content of less than one per cent Langtry 1 found a range in the fusion temperature of from 1900° to above 2750° Fahrenheit, while ash from coal having 4.3 per cent sulphur had a fusion temperature of 2400°. These tests, therefore, show that the amount of sulphur can not be taken as an indication of clinkering tendency. (See fig. 42.) VOLATILE MATTER AND FIXED CARBON The volatile matter shown in the proximate analyses (Tables 13 and 14) consists of those gases which are driven off when the coal is heated to a temperature of approximately 1742° Fahrenheit (950° Centigrade) less the moisture. The residue, less the ash, is called fixed carbon. The true pro- portions of volatile matter and fixed carbon are shown only in a moisture- and ash-free analysis (condition 3 of Table 13). If condition 1 of Table 13 were alone considered, that is moist commercial coal as loaded, weighed and billed at the mine, two lots of coal having apparently the same relative amount of volatile matter and fixed carbon may have total amounts that are different due to difference in moisture and ash content. So far as heat value is concerned volatile matter may have as high or a higher heat value than the fixed carbon, and in large industrial furnaces one should be as efficiently burned as another. Small domestic and some other furnaces do not utilize the volatile material so completely and as a result smoke is produced. SULPHUR Sulphur occurs in coal as organic sulphur which was originally part of the plant material, and also in mineral form of secondary origin. In mineral form it is present chiefly as iron pyrites in nodules, bands, and as thin ver- tical seams in the fine joints of the coal. Some sulphur is also present in the mineral gypsum which occupies thin vertical seams in the coal. This mineral and calcite form the thin white flaky substance commonly seen on a coal face when freshly broken. Sulphur, particularly from iron pyrites, is responsible for the sharp pungent disagreeable gas that occasionally escapes from a domes- tic heating plant, especially when hot clinkers are pulled from the fire. Sulphur is a factor in gas manufacture, as it must be removed from the gas by purification before delivery to the consumer through the distributing system. This has led to the use of low-sulphur coal, and as eastern gas plants Langtry, W. D., The fusion temperature of coal ash: Power, p. 192, vol. 67, 1928. ANALYSES OF COAL 91 R.3W R.1E Scale in miles Coal containing Coal containing- less than 1 per less than 1.25 cent sulphur. per cent sulphur. Fig. 43. Map showing location of low-sulphur coal in the Franklin-Williamson and Big Muddy dis- tricts. The Big Muddy District in Jackson County has been worked out. (Cady, G. H., Low Sulphur Coal in Illinois : Illinois Geological Survey Bulletin 38, fig. 58, p. 432, 1922.) 92 ILLINOIS COAL could easily obtain such coal supplied from comparatively nearby sources, there developed a practise in gas-plant design based on the use of low-sulphur coal. Capacity of purifying equipment considered necessary for a gas plant was based on the use of such coal. These plant designs were adopted as gas manufacture moved westward, with the result that in many small city or town gas plants it is often necessary to use eastern coal ; not that the best Illinois coal would not be more economical fuel, but because of limited purifying capacity. The effect of sulphur on the fusion temperature of ash is discussed on pages 89-90. Sulphur as an article of commerce has many uses and its recov- ery as a salable by-product from gas manufacture is a recent development. Although in general the amount of sulphur in Illinois coal is in excess of 1.5 per cent, there are two areas in southern Illinois, as shown in figure 43, wherein the amount of sulphur is less than 1.25 per cent. In part of the areas, as shown by the map, the coal contains less than 1 per cent sulphur. In the smaller area, that in Jackson County, the coal has been nearly exhausted. Coals from other regions, under careful preparation, may have a sulphur content of less than 1.5 per cent. The map, however, refers to data collected from face samples. A small area of coal No. 5 northwest of Galatia in northwestern Saline County is probably underlain by coal having less than 1.0 per cent of sulphur. The location of the area is known only from drilling as no shafts are oper- ated. Surrounding this area of low sulphur coal is a larger area in which the sulphur content is prevailingly less than 2.0 per cent, but the outline of this area is likewise very imperfectly known. HEATING VALUE (B. t. u.) Inasmuch as coal from different sources may vary in the amount of heat which it can produce, it is very important to adopt a standard measure of heat value. B. t. u. is an abbreviation of British thermal unit, and as here used (Tables 13, 14, 15, and 16) applies to the heat value of one pound of coal, one B. t. u. being the amount of heat required to raise the temperature of one pound of water one degree Fahrenheit. Coal as bought, sold, and supplied to the furnace has a natural moisture content and the only B. t. u. value that should apply in the transaction is that of the moist commercial coal (condition 1 of Tables 13, 15 and 16). Unfortu- nately the use of the B. t. u. value on a dry basis has also become quite gen- eral. This use has led to confusion and has been the means by which buyers not familiar with coal analyses have often been misinformed as to coal values. IMPORTANCE OF ACCURATE B. T. U. DETERMINATIONS It is sometimes thought that two to four per cent variation in B. t. u. tests is of little importance, so it is well to realize the effect of such differences ANALYSES OF COAL 93 as expressed in money. The effect of a four per cent difference on the value of the coal is as follows : 1. Assume coal $2.50 at mine, with freight $3.55 per ton — cost at desti- nation will be $6.05. Four per cent of this sum is 24.20 cents per ton; on 10,000 tons of coal it will amount to $2,420.00. 2. Assume screenings $1.75 at mine, with freight $3.35 — cost at desti- nation will be $5.30. Four per cent is 21.20 cents per ton; on 10,000 tons, it will amount to $2,120.00. 3. On the $1.95 freight rate, coal at $2.50 at the mine will cost $4.45 at destination. Four per cent is 17.80 cents per ton; on 10,000 tons, it will amount to $1,780.00. 4. Screenings on $1.95 freight rate, at $1.75 at the mine, will cost $3.70 at destination. Four per cent is 14.80 cents per ton ; on 10,000 tons, it will amount to $1,480.00. A two per cent variation will affect the value of a coal one-half the above amounts. No large user of coal can afford to ignore differences even as small as two per cent of the B. t. u. value. It is important therefore that such determinations be made with the standard of accuracy of the best laboratories. According to the Report of Committee D-5 on Coal and Coke, American Society for Testing Materials, the permissible difference in calorific value of tests in one laboratory is 0.3 per cent and of different laboratories is 0.5 per cent on the same sample of coal. DETERMINING FUEL VALUES The B. t. u. content is only one of several factors to be considered in the purchase of coal. Another factor is the size of the pieces of coal. The effect of difference in size of coal upon its efficiency as a fuel is given attention in Chapter VI. Another factor is the effect of moisture and ash content on the combus- tion of coal in the furnace. For example, in the case of two coals of the same heat value, the one containing the most moisture has less available heat be- cause of the heat consumed in evaporating- the excess moisture. Likewise, coal with excessive ash gives less heat because of the greater interference with combusion. Therefore, in comparing one coal with another, the commercial B. t. u. may be subject to correction to compensate for excess moisture and ash. 3 In steam boiler practise about 1256 B. t. u. are required in heating one pound of moisture to 212 degrees, evaporating it, and superheating the result- ing steam to chimney temperature. Thus the heat required to remove the ex- cess moisture which one coal contains compared with another is 1256 times the excess moisture for each 100 pounds of coal. 3 Bement, A., Effective B. t. u. and cost determined value of coal: Power, p. 448, September 18, 1923. 94 ILLINOIS COAL At the St. Louis Exposition tests of coal were conducted by the Technol- ogic Branch of the United States Geological Survey (later Bureau of Mines) by burning coal under a boiler on a hand-fired grate. These tests showed that for each one per cent additional dry ash, the effective heat value of the coal as burned in the furnace was reduced by one and one-half per cent. Tests with a chain-grate stoker, 4 as shown in figure 41, page 88, gave, through the usual range of dry ash found in commercial coal, a reduction in value of the fuel of one per cent for each one per cent additional ash. Table No. 12 shows the application of these corrections, using for ash the one per cent correction. Table 12. — Comparison of effective fuel value of two coals Coals A B 1. Moisture 8.90 11.97 2 Excess moisture 3.07 3. Ash in dry coal 9.46 11.97 4. Excess ash in dry coal 2.51 5. B.t.u. by laboratory test 1 1936 10880 6. B.t.u. loss due to excess moisture (Item 2, 1256 times .0307) 38 7. B.t.u. loss due to excess ash (Item 4, 10880 times .0251) 273 8. B.t.u. loss (sum of Items 6 and 7) 311 9. B.t.u. effective (Item 5 less Item 8) 11936 10569 10. Relative value of A and B (10569 divided by 11936, Item 9) 1.00 0.88 11. Mine price assumed for coal A $2.50 12. Mine price derived for coal B $2.27 Coal B at destination should not have a price greater than 88 per cent of coal A. Ultimate Analyses of Coal Along with the proximate analysis there has developed another form of analysis known as the ultimate analysis which expresses the constitution of the combustible portion of the coal in terms of oxygen, hydrogen, carbon, nitrogen and sulphur (Table No. 15). This analysis provides the chemist and user of coal with somewhat more detailed information in regard to the combustible portion of the coal than does the proximate analysis. For instance the amount of oxygen in the ultimate analysis enables one to tell how much of the volatile matter shown in the proximate analysis is moisture and hence not heat producing. All of this oxygen is regarded as being in combination with hydrogen as water of composition, in the ratios by weight of 8 to 1. The remaining hydrogen is known as free or available hydrogen since it is available to the oxygen of the draft for combustion. This 4 Abbott, "W. L., Some characteristics of coal as affecting performance with steam boilers: Journal "Western Society of Engineers, vol. 11, p. 534, 1906. ANALYSES OF COAL 95 combustion of available hydrogen and oxygen supplied by the draft produces heat and water. Water so formed is called "water of combustion". Knowing the ultimate composition of coal it is possible to estimate the amount of air necessary for its complete combustion, carbon, available hydro- gen and sulphur being the substances the oxidation or burning of which re- quires air. It is evident that in calculating the amount of air necessary for the combustion of hydrogen, the amount of available hydrogen as shown in Table No. 16 is the value to be used rather than total hydrogen given in Table No. 15. The amount of oxygen necessary for this reaction is 8 times by weight the amount of available hydrogen. COMBUSTIBLE AND NONCOMBUSTIBLE INGREDIENTS The combustible ingredients are those which upon combining with the oxygen of the draft produce heat and are driven off as gases. These are car- bon, sulphur and available hydrogen. Water of composition and nitrogen are driven off as gases by the heat of combustion but are not themselves combusti- ble. The moisture of commercial coal is also driven off by heat of combus- tion and is noncombustible. Ash is the noncombustible portion which remains when the coal is completely oxidized or burned. Table No. 15 is so arranged as to show the combustible and noncombustible components of coal. The non- combustible elements are grouped together as the first four terms of the analy- sis ; the three combustible elements follow ; leaving for the last the calorific or B. t. u. value. The relations may be expressed as follows : Carbon ) Available Hydrogen v equals combustible Sulphur \ Water of composition ) Combustible plus \ and [ ec l uals moisture " a » d ' Nitrogen ( ash-free coal Moisture- and ash-free coal plus ash equals dry coal Dry coal plus moisture equals commercial coal CONSTANT AND VARIABLE ELEMENTS IN COAL Inspection of Tables 15 and 16 show that there are variations in all items. No two analyses are alike. Yet the amount of variation is quite different among the several items and it is known that variations in the coal and in mining conditions cause greater variations in the amount of certain ingred- ients than it does in others. In other words, there are certain elements which have a fairly characteristic value over considerable areas, provided the vari- 96 ILLINOIS COAL Illinois State Geological Su >u 6 Mchem: - j ^ ■ - J J— J i W'Nnti f i Fig. 44. Map of coal mining districts showing average B. t. u. values of the coal seams. ANALYSES OF COAL 97 able elements are eliminated. The following table shows the constant and variable constituents in coal : Constant elements and Variable elements and combination combination Carbon Hydrogen Sulphur Water of composition Ash Nitrogen Moisture As moisture commonly changes during coal shipment, either decreasing or increasing depending upon the weather, it is common to consider moisture a variable. The moisture content of face samples is, however, as constant for local regions as other items in the analysis. The ultimate analyses include also a statement of calorific or heating value. As the values shown are the same as those given in the tables of proximate analyses and as these latter tables include additional county values the discussion of these values has been included in the discussion of the proximate analyses. STANDARD CALORIFIC VALUES ASH- AND MOISTURE-FREE COAL AND UNIT COAL The B. t. u. value of coal is determined by the combustible elements in the volatile matter and fixed carbon, namely, carbon, hydrogen and sulphur. As the content of carbon and hydrogen remains about constant in a general region, the greatest source of irregularity is the sulphur, the amount of which varies considerably within the same seam. If the sulphur did not vary but was a constant as are hydrogen and carbon, it is apparent that B. t. u. value of coal would vary only in response to variations in the ash and moisture. The ash- and moisture-free B. t. u. value would therefore be a very exact value for each coal in local regions such as counties. All B. t. u. determinations of coal from the same bed in the same county calculated to an ash- and moisture- free basis should closely approximate one another. It is largely because of variations in the amount of sulphur that there are variations in the ash- and moisture-free B. t. u. values within local areas. However, it is believed that county B. t. u. values on an ash- and moisture-free basis for each seam prob- ably come nearer to representing the actual calorific value of the coal than do the values of commercial coal, and average county values based upon such determinations furnish a means of judging the relative accuracy of individual analyses. The ash- and moisture-free B. t. u. value is often called "Pure coal". If a basic value of greater accuracy in comparison is desired the county average unit coal value 5 may be used. This B. t. u. value is the calorific value 6 Parr, S. W., Chemical study of Illinois Coal: Illinois Coal Mining Investigations Bull. 3, p. 52. 1916. 98 ILLINOIS COAL of the coal as mined, corrected for moisture, mineral matter, and sulphur. It is regarded as the most accurate expression that has been devised for the heat value of the pure coal substances. (Item 4 in tables of analyses.) B. T. U. VALUE OF CARBON, HYDROGEN, AND SULPHUR The B. t. u. value of the combustible elements given as the last item in each analysis included in Table 16 is calculated from the known calorific value of carbon, hydrogen, and sulphur. It is not like other heat values determined by actual experimentation but is mathematically derived. The values are of interest only as providing a basis for comparing the theoretical calorific value of the combustible elements in coal. These theoretical values are lower than are the values which are obtained by calculating the derived calorific value of moist commercial coal to a noncombustible-free basis. Figure 44 shows the average B. t. u. value of Illinois coal on an "as received" basis for the mining districts of the State. When heat values are mapped on a "pure coal" basis sharper distinctions can be made in the heat values of the coal produced in the various districts. Mapping is still more refined when done on the basis of "unit coal" values, so that it is commonly possible to differentiate the coal mined in contiguous counties on the basis of the "pure coal," and even more satisfactorily on the basis of "unit coal" values. Although proximate and ultimate analyses are useful as a basis for esti- mating the value of a coal under ordinary conditions of use, that is as a raw fuel, it is believed that in the not far distant future manufactured fuels will be made from coal which in their burning will utilize much more of the fuel value of coal than is possible in burning raw coal. ANALYSES OF COAL 99 Table 13. — County averages of proximate analyses of Illinois coal a 1. Moist Commercial Coal as loaded, weighed and billed at mine. 2. Moisture-free or Dry Coal. 3. Moisture- and Ash-free Coal. 4. Moisture- Ash- and Sulphur-free Coal or Unit Coal expressed in B. t. u. County Coal Number Condi- tion Moisture Ash Volatile Matter Fixed Carbon Sulphur B. t. u. 11.92 16.11 11.31 12.97 12.70 12.37 >.42 11.21 15.09 Interrogated numbers of coal beds are those which are used locally, but which remain to be verified by state-wide studies. a Compiled by the Coal Section of the State Geological Survey from analyses of face samples made by the University of Illinois, the United States Geological Survey, or the United States Bureau of Mines. The Schuyler County coal Nc. 2 average is the only one based on less than three analyses. The county averages represent the average of mine averages, none of which is based on loss than two analyses. Most of the analyses used were made since 1910, none before 1905. Bond 6 1 (one mine) 2 3 4 Bureau 2 1 (three mines) 2 3 4 Christian 1? 1 (one mine) 2 3 4 Christian .... 2? 1 (one mine) 2 3 4 Christian .... 6 1 (four mines) 2 3 4 Clinton 6 1 (six mines) 2 3 4 Franklin 6 1 (twenty-two mines) 2 3 4 Fulton 1 1 (one mine) 2 3 4 Fulton 5 1 (thirteen mines ) 2 3 4 10.73 35.15 42.20 3.39 10,796 12.18 39.91 47.91 3.85 12,257 45.45 54.55 4.38 13,957 14,239 7.41 38.44 38.04 2.92 10,896 8.83 45.82 45.35 3.48 12,989 50.26 49.74 3.82 14,247 14,469 8.86 38.89 40.94 2.34 11,602 9.99 43.85 46.16 2.64 13,082 48.71 51.29 2.93 14,534 14,756 6.92 39.17 40.94 3.13 11,591 7.95 45.01 47.04 3.60 13,318 48.90 51.10 3.91 14,468 14,690 10.20 36.95 40.15 3.91 10,863 11.68 42.33 45.99 4.48 12,443 47.93 52.07 5.07 14,088 14,389 10.23 35.48 41.92 3.36 10,877 11.67 40.49 47.84 3.84 12,413 45.84 54.16 4.35 14,053 14,329 8.54 33.91 48.13 1.45 11,797 9.43 37.43 53.14 1.60 13,024 41.23 58.77 1.77 14,380 14,554 10.21 38.42 40.16 4.96 11,470 11.50 43.27 45.23 5.59 12,918 48.89 51.11 6.32 14,597 14,956 11.02 35.45 38.44 3.22 10,486 12.98 41.75 45.27 3.79 12,349 47.98 52.02 4.36 14,191 14,493 100 ILLINOIS COAL Table 13. — Proximate analyses — continued County Coal Number Condi- tion Moisture Ash Gallatin (north of Eagle Valley) (two mines) 5 1 2 3 4 Gallatin (Eagle Val- ley only) (three mines) 6 1 2 3 4 Greene 4? 1 (two» mines) 2 3 4 Grundy (three mines) 2 1 2 3 4 Henry (four mines) 1 1 2 3 4 Jackson (Murphysboro District only) (five mines) 2 1 2 3 4 Jackson 6 1 (one mine) 2 3 4 Jefferson .... 6 1 (one mine) 2 3 4 Knox (two mines) 1? 1 2 3 4 Knox 4 1 (one mine) 2 3 4 LaSalle 2 1 (seven mines) 2 3 4 4.85 5.77 14.43 17.20 15.84 9.28 9.43 Volatile Matter Fixed Carbon Sulphur B.t. u. 11.10 35.58 48.47 3.42 12,327 11.67 37.39 50.94 3.59 12,955 42.33 57.67 4.06 14,667 14,956 10.88 35.92 47.43 3.84 12,346 11.55 38.12 50.33 4.08 13,102 43.10 56.90 4.61 14,822 15,136 9.42 36.14 40.01 3.91 10,890 11.01 42.23 46.76 4.57 12,727 47.45 52.55 5.14 14,302 14,601 5.22 38.23 39.35 2.27 11,112 6.31 46,17 47.52 2.74 13,420 49.28 50.72 2.92 14,324 14,488 9.00 37.08 38.08 4.75 10,658 10.69 44.06 45.25 5.64 12,664 49.33 50.67 6.32 14,180 14,507 5.72 33.99 51.01 1.29 12,489 6.31 37.47 56.22 1.42 13,766 39.99 60.01 1.52 14,693 14,820 9.77 34.69 46.11 2.06 11,607 10.79 38.30 50.91 2.27 12,816 42.93 57.07 2.54 14,366 14,584 8.7 34.6 48.2 1.3 11,980 9.5 37.8 52.7 1.4 13,090 41.8 58.2 1.6 14,460 14,630 7.94 36.70 41.08 4.54 11,167 9.26 42.81 47.93 5.30 13,027 47.18 52.82 5.83 14,356 14,653 7.73 37.97 39.32 3.87 11,222 9.09 44.66 46.25 4.55 13,199 49.13 50.87 5.00 14,519 14,794 8.56 38.28 38.60 3.36 11,022 10.02 44.80 45.18 3.93 12,900 49.79 50.21 4.37 14,337 14,599 14.28 14.98 14.56 Interrogated numbers of coal beds are those which are used locally, but which remain to be verified by state-wide studies. ANALYSES OF COAL 101 Table 13. — Proximate analyses — continued County Coal Number Condi- tion Moisture Ash Volatile Matter Fixed Carbon Sulphur B.t. LaSalle 5(6?) 1 (one mine) 2 3 4 LaSalle 7 1 (one mine) 2 3 4 Livingston . . . 5? 1 (two mines) 2 3 4 Logan 5 1 (two mines) 2 3 4 Macon 5 1 (two mines) 2 3 4 Macoupin .... 6 1 (eleven mines) 2 3 4 Madison 6 1 (seven mines) 2 3 4 Marion 6 1 (three mines) 2 3 4 Marshall .... 2 1 (two mines) 2 3 4 *Marshall . . . 7 1 (six mines) 2 3 4 14.76 13.56 11.59 13.50 13.89 13.32 13.04 10.31 15.10 15.29 9.65 41.33 34.26 3.38 10,674 11.32 48.49 40.19 3.97 12,522 54.67 45.33 4.48 14,120 14,399 7.77 40.87 37.80 3.68 11,347 8.99 47.28 43.73 4.26 13,127 51.95 48.05 4.68 14,424 14,684 12.65 35.73 40.03 3.94 11,054 14.31 40.41 45.28 4.46 12,503 47.16 52.84 5.20 14,591 14,959 10.64 36.84 39.02 3.16 10,740 12.30 42.59 45.11 3.65 12,416 48.56 51.44 4.16 14,157 14,442 10.21 36.18 39.72 3.42 10,701 11.86 42.02 46.12 3.97 12,427 47.67 52.33 4.50 14,099 14,385 9.80 37.42 39.46 4.00 10,736 11.31 43.17 45.52 4.61 12,386 48.68 51.32 5.20 13,965 14,259 10.03 37.96 38.97 4.02 10,813 11.54 43.65 44.81 4.62 12,434 49.35 50.65 5.22 14,056 14,357 11.06 36.55 42.08 3.80 11,227 12.34 40.75 46.91 4.24 12,517 46.49 53.51 4.84 14,279 14,590 7.18 39.08 38.64 2.79 11,312 8.46 46.03 45.51 3.29 13,324 50.29 49.71 3.60 14,555 14,777 14.12 35.27 35.32 3.51 10,053 16.67 41.63 41.70 4.13 11,868 49.96 50.04 4.96 14,242 14,627 Interrogated numbers of coal beds are those which are used locally, but which remain to be verified by state-wide studies. * Based on analyses by University of Illinois and/or TJ. S. Bureau of Mines of face samples collected under supervision of State Geological Survev in co-operation with Zeigler Coal and Coke Company. 102 ILLINOIS COAL Table 13. — Proximate analyses — continued County Coal Number Condi- tion Moisture Ash Volatile Matter Fixed Carbon Sulphur B. t. u. McDonough . . 2 1 16.63 8.30 34.19 40.88 2.94 10,804 (two mines) 2 9.96 41.01 49.03 3.53 12,959 3 45.55 54.45 3.93 14,392 4 14,642 McLean 2 1 11.27 8.80 42.21 37.72 3.03 11,566 (one mine) 2 9.92 47.57 42.51 3.41 13,035 3 52.81 47.19 3.79 14,470 4 14,717 McLean 5 1 13.32 12.47 38.00 36.21 3.73 10,580 (one mine) 2 14.38 43.84 41.78 4.30 12,206 3 51.20 48.80 5.02 14,256 4 14,605 Menard 5 1 16.25 8.77 36.34 38.64 3.37 10,521 (one mine) 2 10.47 43.39 46.14 4.02 12,562 3 48.46 51.54 4.48 14,030 4 14,293 Mercer 1 1 15.64 8.97 38.51 36.88 4.44 10,747 (four mines) 2 10.63 45.65 43.72 5.26 12,739 3 51.08 48.92 5.88 14,254 4 14,570 Montgomery . . 6 1 13.26 10.02 36.33 40.39 4.27 10,725 (six mines) 2 11.55 41.88 46.57 4.92 12,365 3 47.35 52.65 5.56 13,979 4 14,288 Moultrie 6? 1 6.73 11.60 39.06 42.61 4.16 11,906 (one mine) 2 12.44 41.88 45.68 4.46 12,765 3 47.82 52.18 5.09 14,579 ■4 14,911 Peoria 5 1 14.61 11.10 35.05 39.24 3.11 10,661 (seven mines) 2 13.00 41.05 45.95 3.64 12,485 3 47.18 52.82 4.18 14,351 4 14,654 Perry (east) a 6 1 10.32 9.38 33.01 47.29 0.92 11,445 (two mines) 2 10.46 36.81 52.73 1.03 12,762 3 41.11 58.89 1.15 14,253 4 14,421 Perry (west)« 6 1 10.09 10.66 36.19 43.06 3.34 11,142 (ten mines) 2 11.86 40.25 47.89 3.71 12,393 3 45.67 54.33 4.21 14,061 4 14,336 Randolph .... 5? 1 10.73 10.35 36.38 42.54 4.31 11,150 (two mines) 2 11.60 40.75 47.65 4.83 12,490 3 46.10 53.90 5.46 14,128 numb( 4 >rs of ( ;oal beds s Lre those \ ^hich are i ised locall y, but whi< 14,441 Interrogated ih remain to be verified by state-wide studies. a There is a difference in quality on the east and west of the Duquoin anticline. ANALYSES OF COAL 103 Table 13. — Proximate analyses — continued County Coal Condi- Moisture Ash Volatile Fixed Sulphur B. t. u. Number tion Matter Carbon Randolph .... 6 1 10.07 11.63 36.72 41.58 3.96 10,988 (four mines) 2 12.93 40.83 46.24 4,40 12,218 3 46.89 53.11 5.05 14,032 4 14,349 Rock Island . . 1 1 16.61 8.48 35.66 39.25 4.82 10,615 (one mine) 2 10.17 42.76 47.07 5.78 12,729 3 47.60 52.40 6.43 14,170 4 14,493 Saline 5 1 6.68 8.39 34.25 50.68 2.55 12,406 (sixteen mines' ) 2 8.99 36.70 54.31 2.73 13,294 3 40.33 59.67 3.00 14,607 4 14,818 Sangamon .... 5 1 14.10 1 [0.52 36.41 38.97 4.00 10,657 (nine mines) 2 12.25 42.39 45.36 4.65 12,406 3 48.31 51.69 5.30 14,138 4 14,456 Sangamon .... 6 1 13.91 9.96 36.91 39.22 4.13 10,696 (three mines) 2 1 11.57 42.87 45.56 4.80 12,424 3 48.48 51.52 5.43 14,049 4 14,357 Schuyler .... 2 1 12.53 7.54 37.84 42.09 4.54 11,731 (one mine) 2 8.62 43.26 48.12 5.19 13,411 3 47.34 52.66 5.68 14,676 4 14,973 Schuyler .... 5 . 1 15.19 9.88 34.69 40.24 2.65 10,844 (one mine) 2 1 1.65 40.90 47.45 3.12 12,786 3 46.29 53.71 3.53 14,472 4 14,737 Shelby 5 1 11.21 10.74 35.24 42.81 3.58 11,071 (one mine) 2 12.10 39.69 48.21 4.03 12,469 3 45.15 54.85 4.58 14,185 4 14,481 St. Clair 6 1 11.12 11.32 37.95 39.61 3.80 10,972 (ten mines) 2 12.73 42.70 44.57 4.27 12,345 3 48.93 51.07 4.89 14,146 4 14,458 Tazewell .... 5 1 1 5.14 9.47 35.72 39.67 3.20 10,735 (two mines) 2 11.16 42.09 46.75 3.77 12,650 3 47.38 52.62 4.25 14,239 4 14,512 Vermilion . . . 6? 1 ] 4.42 9.32 35.16 41.10 2.49 10,942 (five mines) 2 • 10.89 41.08 48.03 2.91 12,786 3 46.10 53.90 3.26 14,349 4 14,590 Interrogated numbers of coal beds ai^e those which are used locally to be verified by state-wide studies. but which remain 104 ILLINOIS COAL Table 13. — Proximate analyses — concluded County Coal Number Condi- tion Moisture Ash Volatile Matter Fixed Carbon Sulphur B.t. 13.29 13.15 10.12 8.54 15.28 6.96 6.69 Interrogated numbers of coal beds are those which are used locally, but which remain to be verified by state-wide studies. Vermilion . . . 7? 1 (two mines) 2 3 4 Warren 1 1 (two mines) 2 3 4 Washington . . 6 1 (two mines) 2 3 4 White 6 1 (one mine) 2 3 4 Will 2 1 (one mine) 2 3 4 Williamson. . . 5? 1 (one mine) 2 3 4 Williamson. . . 6 1 (twenty-eight mines) 2 3 4 9.82 37.59 39.30 2.84 11,151 11.33 43.35 45.32 3.28 12,860 48.89 51.11 3.70 14,503 14,770 8.57 39.42 38.86 5.49 11,224 9.87 45.39 44.74 6.32 12,924 50.36 49.64 7.01 14,339 14,683 11.71 38.40 39.77 4.14 10,987 13.03 42.72 44.25 4.60 12,224 49.12 50.88 5.29 14,055 14,382 8.96 35.37 47.13 2.86 11,918 9.80 38.67 51.53 3.13 13,031 42.87 57.13 3.47 14,447 14,681 5.57 33.86 45.29 1.80 11,287 6.57 39.92 53.51 2.12 13,323 42.75 57.25 2.26 14,260 14,407 11.17 34.00 47.87 3.50 11,890 12.00 36.53 51.47 3.76 12,779 41.53 58.47 4.27 14,522 14,818 9.45 36.01 47.85 3.55 12,025 10.12 38.60 51.28 3.81 12,887 42.95 57.05 4.24 14,338 14,598 ANALYSES OF COAL 105 3 2 1 ' - -~— — C3 ^ rt Vj t-5 Zi ^> -§ £ £> „ s 3* i o S ON * ^f On CM On O t^ o NO »~1 On co i-H ON ON r^ CM CO t^ to On Tf O CM J>. CM CO CO Tf CVJ to CO m T-H lO «* -«*■ Tl- Tf Tt Tf rr ^T -*■ Tf Tf NO SO NO vo lO O Tf oo m iO o CM <* On o o rH O rH O O CO o oo CO ON LO CO o co Tt" t^ ON ON ^1- 00 o vo to «— > CM CO CO CO CO CO CO CM CM co Tf CO VO CM 00 CO CO o VO CO CO 00 CO rt- to CM , 1 co o o LO t^ CM o «— 1 CO VO r^ VO o 1 — 1 ON CO in o to CO CO -r rt- CO rt" hJ o CO VO ON o ►J (VI o i^ LO 00 CM oo to to r^ CO < «* CO CO CO CO 00 u o J>^ to CM CM ON 00 rr VO CO 00 CO VO CM O VO ON co co CM On co to CM rt ON CM On co co T-H rf CO co vo "? ni ■ - c f °? rt <£ X! cd S •= ^ fa £ £ rt a &fg •? ? g i; ? w " O v^- ^ 5 J -1 h-S o S rt s *o fe y. OS |8..S o i- •? OJ Jj ;3l rt a v rt hJ . .£ rt > u H. 3 O >> a TJ o C Q c nJ >. P v / •2 -a £ U c 3 o 3 o Q ^-^ Oh CO u rt 106 ILLINOIS COAL § .s <^ ; — •Tr- ,n CS fc* T3 S-i ?*> a * x) ] T1 to OJ s *tt 1 03 O *» ei S ■£» Ih g cj C *d s s C3 CM rd © u & cu b O ti !< ( ) -^ u to s — ' Cm w x to & X £ u CO O S ?fi N "*■* £«! « (S 1=1 oJ S en » ON oo C/i CO On "* © K t< ON CO vd ON VO O CO LO CO vo CO VO CO CO VO LO 00 ON ON 00 ON LO T-H ^ N fO CO ON ^ CO ON Tj- Tf Tl- rt- lo h csi 't ex. r-t OJ Tf S^| O HH en O ft o « r N ft 03 — H "C s O rt ^ ft o3 cu rn "Jh o ■P J3 o Oj rrj I i ^ ft ft CL> 3 q^ o x; o U O (J mm m . 03 J3 c c O O U U J2 j= : u >> c 3 CQ O s - / rfS •a s 03 O bfl rt o3 cC§ O 03 c3^ C/3 5 u U U O in ri O V iS ^ p c S £ 03 O > ^ •S S o3 .S U Pd U PQ oi ANALYSES OF COAL 107 ~-> -o o bo ■c o3 lg s ^ 1! •I I 5 s ^ _ '5 *a3 Q , £G t/5 'o c u s u to s 0) Ih J3 C/5 ■4-5 3 < PQ *Oj O U ■*"* rt s ■~A < i - ° Si u o 1 3 .» € .3 S ,.SP t u > ^ "§13 *S - £- >> o3 to « > |> ^ 03 3 rt 03 rp H c .2 T3 O C /-n w C 03 cfl .Si - § & S 03 o ~ •~ 03 W O o3 lII ^ to « oo c P ^ § o3 hfl o ^ ri U to s NO oo 00 '—1 Tt to l-H I 1 o 02 ON ON a •(-> & m ON w *J rf Tt >> c '"■ ' p ■0 s 0) u o 00 NO > >i O 00 CM cm" On cm" .a > u o g "c3 £ 02 "3 o o m CM u o rf a> CO co 09 c CM O 3 02 (D > © 00 X5 T3 ta ON CM a> M Tf to ^ +J a> £3 fl DO o o P c3 o o "O + J NO CM Jh a) h s > c3 I— 1 ce ^3 tM . "^ © CO ^ a aj t A ■a c