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 Floating Minute Organic Matter in the Air 
 
 AND ITS MANAGEMENT TO PREVENT 
 
 Disease and to mitigate or control it, with a new 
 
 DEVICE FOR 
 
 ATMOSPHERIC PURIFICATION. 
 
 -;WITH AN ORIGINAL ILLUSTRATION,:- 
 
 By David Prince, M. D., of Jacksonville, Illinois. 
 
 As to the number of microbes in the air, some reliable infor- . 
 mation is to be obtained from some recent observations by M. 
 Miguel in a publication reviewed by M. Hacbe in the Revue de 
 Chirurgie for May and June, 1884. 
 
 By these observations, what was known before in relation 
 to the influence of the weather is further confirmed. 
 
 The spores of the mould and cryptogams arc especially vari¬ 
 able, being most prevalent in damp weather. On the other hand, 
 the 8ej)tie microbes are least abundant during the rainy periods 
 and most abundant during the periods of drouth. 
 
 The average number of microbes found in the air at M^t 
 Souris ( near Pari.s ) was 84 to the cubic metre of air. In ap¬ 
 proaching the centre of the city, the number was found to in¬ 
 crease, being ten times that outside of tlio city. 
 
 A series of observations was made at the top of the Pantheon, 
 250 feet high, which showed that the air was more pure there 
 than at M’t Souris, and ten times less charged with microbes 
 than that on the surface in the centre of the city. 
 
 In the interior of the well-kept habitations, the microbes in¬ 
 crease during cold weathfer at the same time that they diminish 
 in the free atmosphere. 
 
 To give an example of the enormous aecurnillation in appar¬ 
 ently well-kept houses in populous centres, observations were 
 made in the lourth story of a house recently built, in a bed- 
 
 Reprinte,d from the St. Louis Medical and Surgical Joui'naf February.^ 1885* 
 
— 2 - 
 
 room occupied only twelve hours of the twenty-four, and there 
 was found to be the large number of 526 microbes to the cubic 
 metre of air, while in a room similarly situated at Ml Souris 
 there were only 325. 
 
 In hospitals,‘microbes have been found by M. Miguel to the 
 number of 6,300 to the cubic metre. At the Hotel Dieu, 5,123 
 in the summer and at the Hopital cle la Pitic an average, by 
 the year, of 11,100. 
 
 The microbes found in surgical wards abound especially in 
 the form of micrococcus. The microbes cultivated and inoculated 
 into animals generally proved harmless, but in some rabbits and 
 guinea pigs, grave affections were produced. 
 
 The dust deposited upon objects waa found to contain mi¬ 
 crobes to the number of 750,000 1 ) 1,300,000 to the cubic metre. 
 
 The question is discussed by the author and his reviewer, 
 whether the different forms of microbes are originally of differ¬ 
 ent species and varieties, or whether they are capable of develop¬ 
 ing or degenerating from one form and character into another. 
 M, Miguel, M. Cohn and M. Noegali are quoted as having 
 investigated the subject, the latter of whom is quoted thus: 
 ‘‘I am well convinced that too many species have been dis¬ 
 tinguished among the schismocetes. It seems to me, on the 
 other hand, somewhat probable that all the schismocetes consti¬ 
 tute one natural species. There may exist among them a small 
 number of genera or species now recognized of which each 
 passes through a cycle of forms. 
 
 M. Hache goes on to say, that successive cultures can pro¬ 
 foundly modify the mode of their physiological activity. 
 
 Examples are quoted of the metamorphosis of the compara¬ 
 tively innocent hay bacillus (or bacdlus subtiiis) into the microbe 
 oranthrax or splenic fever, which is one ot the most virulent of 
 the yftthogenic forms. 
 
 Finally, the cultivations of Pasteur are referred to as a proof 
 of this position. On the other hand, Klein, in a series of articles 
 in recent.n unbers of the Practitioner, which have been published 
 also by McMUlan in book form, claims that in those cultures in 
 which septic microbes seem to have been converted into pathoge¬ 
 nic microbes, and vice versa, there has not been sufficient care to 
 secure purity of ulture; that the kinds have become mixed to 
 such an extent as o destroy the value of the observations. 
 
 Many carefully, made observations and noino diagrams are 
 
^presented in the article by M. Mii^iiel to show that, in the main, 
 the amount of disease prevailing among people is proportionate 
 to the number of minute organisms floating in the air; the 
 greater amount of mortality in tie centre of large ci^Jes corres¬ 
 ponding with the greater number of floating microbes. 
 
 One reason for this may be that cities furnish iniJecaying 
 organic substances, the culture media, for the propagation of 
 the dangerous forms of microbes, while in the country the decay¬ 
 ing material is chiefly vegetable and fitted for the development 
 of the zymotic and septic varieties, and equally unfiitod for the 
 development of those microbes which are known to produce 
 specific diseases, the most common of which is erysipelas. 
 
 According to present knowledge, the organic objects floating 
 in the air may’be classified as : 
 
 1. The spores of objects many of which are to be seen with 
 low powers. These became familiar to the earliest observers 
 with the microscope, as the yeast plant .—Zymoitc Agents, . 
 
 2. The spores and sometimes the developed forms of a class 
 requiring higher and sometimes the highest powers to see them, 
 which produce in nitrogenized organic material the phenomena 
 of putrefaction but have no power of attacking living tissue. As, 
 bacterium termo, hay bacillus —Septic Agents, 
 
 3. The spores and sometimes the developed objects of a class 
 generally requiring high powers for their observation, which pro¬ 
 duce, when introduced into living tissues, or their fluids, changes 
 characterized by the phenomena of special disorders, as erysipe¬ 
 las, hospital gangrene, anthrax, tuberculosis, etc .—Pathogenic 
 Microbes, 
 
 In the following named diseases, this contagium has be-n 
 proved to be particulate and vital, capable of mutiplying and 
 perpetuating its kind when temperature and sustenance i^^nder 
 it possible. 
 
 These are, various septic developments, and erysipelas, hos¬ 
 pital gangrene, small-pox, diphtheria, gonorrhcea, Koch^s septi- 
 ciemia of mice, Davaine's septicaemia, chicken cholera, swine 
 cholera, leprosy, Koch^s malignant oedema, 8 nthrax, actinomy¬ 
 cosis, tuberculosis, relapsing fever and Asiatic cholera. The 
 last lacks the proof of successful inoculatio as after a series of 
 cultivations. 
 
 From this it is probable that all other contagious and in fee- 
 
—4 
 
 I 
 
 ) 
 
 \ 
 
 I 
 
 tious diseases are originated a*hd repeated by the action of simi- / 
 lar particulate vital agencies. 
 
 DIGESTION. 
 
 Dr. G. y. Black, in his book on ‘‘The Development of Poi¬ 
 sons through Micro-Organisms has helped to generalize the 
 conception of the manner in which living things appropriate nu¬ 
 triment from surrounding food material. The amoeba converts a 
 portion of its exterior into a temporary stomach by investing 
 an object sufficiently small and digesting it, so that the nutritive 
 elements of it may be absorbed. In accordance with the same 
 idea, an object smallei *han a blood cell comes in contact with 
 the tissues of the body. If the Vi^al condition of the tissue is 
 sufficiently strong, the minute object may be digested. If, on the 
 other hard, the vital force is weak, the cell, with which the 
 invader comes in contact, is digested and the invader by natural 
 increase becomes a spreading colon}', appropriating more and 
 more of the adjacent substance. If several individual invadei’s 
 gain entrance at tiio same time, the conquest is more rapid. It 
 a])pears from the researches of Pasteur, Koch and others, that 
 differert microbes have different degrees of power in the attack. 
 The septic micrococci, bacteria, and bacilli being only capable of 
 attacking i^^aterial destitute of presontvitality, while they are in¬ 
 capable of invading living substance. 
 
 There are minute living object=^, most commonly floating in 
 the air, of many species or varieties and capable of living upon 
 albuminoid material. In accordance with this idea, a blood clot 
 exposed to thp air and left in the wound may become the seat of 
 se})tic changes, w hile the lips of the same wound brought together 
 without any intermediate clot, thou^^h exposed to the samegerm- 
 bcai’ing atmospheric contact, may digest the invading organ-| 
 isms and heal by the firist intention. The blood clot, however, 
 having no such vital power of resist mce, may go into a state of 
 putrefaction and become a source of irritation and infection to 
 the adjacent living surface. Again, f the supposed blood clot is 
 secluded from air containing organisms, or if the vitality of these 
 Invaders is neutralized by some antiseptic agent, as carbolic acid 
 or mercuric bichloride, the clot fails to go into putrefaction and 
 becomes pene rated by a living projecting growth, secreting a 
 soluble ferment, by which the clotiu digested and brought into a 
 condition of solution to be absorln I j. nd carried away. In this 
 
 '4 
 
— 5 — 
 
 view, the question of the innocence of : biood clot turns u}3on 
 the fact of its exposure to the atmospherii 'rfranisms in a condi¬ 
 tion in which they can appropriate its nn ritive material and 
 thrive upon it. If, in a peritoneal cavity, a clot has had such an 
 exposure it will probably go into a conditioi of putrefaction. li', 
 on the other hand, through the absence of or .nanisms brought by 
 the air, or through their neutralization by a-i ' iseptic agents, the 
 seeds of putrefaction are absent or inactive, the clot will become 
 ultimately permeated by leucocytes, dige^ ed and absorbed. 
 The same thing happens with catgut ligatures, with sponge, or 
 other substance which the tissues have the } r»wei of dissolving 
 by the production of an appropriate digestive liuid. Oatgut may 
 be said to bo easy of digestion, so that it dir- ppear." in few days. 
 Silk is more difficult of digestion and is, the!*ei'orc, more i ible to 
 result in an abscess for its ultimate expulsion. Linen is more 
 difficult still of digestion and, therefore, more liable than silk to 
 the formation of an abscess. Silver is again aL'’olutely indiges¬ 
 tible, while it is unirritating and may innoceniiv remain any 
 length of time in contact with living tissue. 
 
 A catgut ligature or a blood clot containing septic germs, is 
 almost certain to proceed to putrefaction, unless from the small¬ 
 ness of volume, the living tissues may be capable of -jurrounding 
 the germs and infiltrating the clot, catgut or other substance con¬ 
 taining them, with a digesting agent capable of destroying the 
 vitality of the microbes; of dissolving and carrying away both 
 them and their store of food. 
 
 As these agents, either in their developed cij in their germ 
 state, float everywhere 'ti the air without the possibility, by any 
 means hitherto practiceu, of completely excluding them, except 
 on a very small scale, thMr entrance to some extent into every 
 open wound is a matter of course. 
 
 This consideration po-nts to the importance of the employ¬ 
 ment of local antiseptics during the progress of t>peration8 atten¬ 
 ded by incisions and as long afterwards as the wound remains 
 open. The antiseplics ; re employed in the form of spray or of 
 a continuously flowing stream. 
 
 The danger is greater when the invaders are not simply the 
 /agents of sepsis, but ar«> the paihogenic microbes of erysipelas, 
 hospital gangrene or other infecuous disease. 
 
 ‘ These are proved to hav 3 a capability of attacking living tis¬ 
 sues and of nroducing by the employment of a stronger diges- 
 
 / 
 
— 6 — 
 
 tivo agenl,, the destruction and appropriation of live cells and 
 dxed tisSuo, without any other natural limit than the whole extent 
 of thel t^y attacked. 
 
 If %ae invading agent be very small in amount and the vital 
 conation of the patient be perfect, the invaders, if not repulsed 
 ov destroyed in the very entrance, may be limited to the forma- 
 iOn of an abscess, while, if the vitality of the patient be feeble, 
 the smallest invasion may end in the complete destruction of the 
 system. This may be the reason why a dissecting wound pro¬ 
 duces a minute abscess in one person, an abscess with a slight' 
 fever in a second, and a fatal blood-poisoning in a third. The 
 difference lies in the power of resistance, and not in the nature of 
 the invaders. 
 
 The use of medicinal agents taken by the mouth cr ijijected 
 into the tissues and vessels has for its object the increase of the 
 power of resistance, as when we combat erysipelas by the inter¬ 
 nal employment of chloride, of iron. 
 
 The local applications, on the other hand, generally have for 
 their object the destruction of the invading agents. 
 
 The local agent applied in anticipation may, however, have a 
 two-fold effect; first to destroy or render inactive the atmosphe¬ 
 ric living agents, and next to preserve the vitality of the incised 
 or lacerated surfaces, so that tLo invaders may be destroyed by 
 the defensive fluid secreted by the living surfaces. 
 
 A stream of the aqueous solution of carbolic acid of the 
 Btrength'of 1 to 100, of mercuric bichloride of a strength of 1 
 to 1,000, or 1 to 10,0-^K) does t necessarily destroy the spores 
 of septic and pathogenic microbes, but it destro\’8 the present 
 activity of those which are in a developed and active condition. 
 It at the same time preserves the moisture and the unimpaired 
 condition of the exposed surfaces, so that the invading germs arc 
 immediately surrounded by a secretion of a strong character 
 ^ \ which invests the invading germs and digests them. A stream 
 of pure water would have the same effect upon the incised or 
 J^cerated surface, only to be sure of its freedom from organic life 
 V " iti^nnsthave been recently boiled for more then thirty miuutes. 
 ^vlciii Tn his little book recently published,* slates that distilled 
 Wi;fer beximes in a few hour’s full of septic microbes in an active 
 devoiOpep state, ready to multiply and flourish when introduced 
 
into any substance furnishing oxygen, nitrogen, and hydrogen, 
 i. e. any natural animal or vegetable substance. 
 
 There are numerous illustrations of the powei if* rp. istance 
 of living tissues against organisms which are sim^^My^ septic in 
 their character. '^ 
 
 It is probably rare that a h^'podermic injection ot 4 iny sub¬ 
 stance is made without introducing at the same time a bubble ol 
 air containing a colony of micro-organisms, either as germ* or in 
 a developed condition; yet the formation of an abscess ? r a 
 more severe general septic poisoning is an exceedingly rare 
 currence. These agents must be devoured as they are surrounded 
 by a stronger vitality. 
 
 The introduction of air on a very large scale occurs after 
 wounds connecting the respiratory passages with the surround* 
 ing connective tissue, and yet the air is generally absorbed with¬ 
 out evil consequences. 
 
 However, if instead of common air it be loaded with the 
 floating products of erysipelas, puerperal or other septic fevei- 
 or hospital gangrene, the hypodermic injection might introduce 
 an enemy of greater destructive force, capable of appropriating 
 and living upon the surrounding cells and fixed tissues, the vi¬ 
 tality of which it overmasters. 
 
 Again, if the patient is in a condition of very feeble vitality, 
 the minute blood clot occasioned by the point of the needle nsay 
 afford an insufficient resistance to the relatively superior vital 
 force of the invading microbes, though only of the septic class. 
 
 In view of these facts and reasons, the most important consi¬ 
 deration in relation to surgical (or accidental) wounds is the 
 purity of the atmosphere, or its freedom from microbes, especi¬ 
 ally those of a pathogenic nature. The latter are very apt to be 
 present in houses which have been contaminated by erysipelas 
 and by those septic fevers which are attended by the presence of 
 pus in a putrefactive condition, while the out-door air or the air 
 of an apartment not used for dwelling purposes, is likely to liave 
 only those microbes which are capable of starting putrefactior 
 in non-vital animal and vegetable substances. 
 
 The second most important consideration is the h jalth of the 
 patient, or his power of resisbnice to the ordinary septic influ¬ 
 ences which are almost everywhere present. 
 
 The power of medicines to increase the resistance is not here 
 paroper subject to consider j suffice it to say, that 'a greal^consid- 
 
eration is the neutralization of the latent malarial poison ready 
 to develop on any occasion of depressed vitality. 
 
 The management of diet is of equal importance, but not in 
 . the scope of consideration to be entertained here. The diet which ^ 
 for the time secures the best state of health, or the management 
 which secures a demand for nutriment and a capability of diges¬ 
 tion and assimilation, are expr *-^ive of the end to be secured. 
 
 The third consideration is t of the local management of a 
 wound —There are three things ; (1.) to protect the surface from 
 drying and the consequent tendency to die and become the seat 
 of septic changes. This is done by a spray or by irrigation, or 
 by the presence of a clot which should not needlessly be wiped 
 off until the time for the final dr ‘ssing. 
 
 (2.) The presence, in the fluid of the spray or irrigation, of 
 some agent which d-'stroys or temporarily neutralizes the float¬ 
 ing organic substances in the atmosphere. It is probable that 
 the best agent yet tried for the purpose, is an aqueous solution 
 of mercuric bichloride, and, as the result of experience, a strength 
 of 1 to 10,000 for a prolonged contact. 
 
 The agent can be applied without injury to the vitality of 
 the exposed wound surtaces, and while too weak to destroy the 
 vitality of the eporc'^ of pathogenic microbes, it is suflSciently 
 strong to nullify their present activity and prevent the immediate 
 production of their digestive soluble ferment. The substances to 
 be applied to wouniis to prevent subsequent septic development 
 arc boric acid and iodoform. The latter is capable of being intro¬ 
 duced into a wound without interfering with union of the sur¬ 
 faces by the first intention. 
 
 The iodoform is ultimately disposed of along with the mate¬ 
 rial of the coagulum which envelops it. The investment of the 
 wound with borated cotton affords a material which retards or 
 prevents putrefaction in the effusions and exudations escaping 
 from the wounds by openings or through drainage tubes. 
 The borated cotton receives these products and prevents their 
 putrefaction, thus affording a material for a dry dressing which 
 makes it practicable to subject a wound to dressings at infrequent 
 times. The baking slowly of borated or sublimated cotton un¬ 
 til it assumes a light brown color, is found to afford a dressing 
 in which the exudations which have escaped from a wound and ^ 
 become dry do not putrefy. ■ 
 
 Ix t^a wet dressing, there is nothing yet known superior to a , 
 
drip of carbolic acid of one^er cent, strength, applied coit'^ Sntlj)' , 
 or at times not more than 20 minutes apart, in order that the^ifes- 
 ence of the agent may be perpetual. ' This is incapable of desttc^- , 
 ing spores, but is yet strong enough to prevent the activity or 
 vital manifestation of the septic microbes, and is probably capable 
 of suppressing the vital manifestations of those of a pathogenic 
 charat ter, or those having the power of producing specific dis¬ 
 eases. a.s those of eiysipelas, hospital gangrene and other dis¬ 
 ease.'^, many of which have not yet been carefully studied, while 
 yet the applications are weak enough not to injure the surfaces 
 to which they are applied. 
 
 Ii s not the purpose of this paper to go much into detail, but 
 to indunt-e in a brief way, the advance of thought upon the sub¬ 
 ject, fused upon the careful investigations .which have proved 
 beyond dispute the dependence of many diseased manifestations 
 upoi. the presence of micro-organisms. 
 
 Tiie conception of digestion, as the means by which micro- 
 orgfiKi.sms are enabled to attack and live upon substances that 
 go ini'! decomposition in connection with their growth and mul- 
 tipl'-axiou, is further developed by Dr. Black in his book,* pp 
 50 A: 85. 
 
 C^iuming from Lister,-}* he states that this observer found that a 
 few germs, of the species of bacterium found in the hydrant water 
 
 I f London, contained in a single drop of water, could not start 
 kcomposition, but a larger amount could. At the same time, the 
 piallest amount of putrid material would start decomposition, 
 he explanation approached by Lister and clearly stated by Dr. 
 Black, is that in the detached state, a bacterium is not able to 
 develop a ferment in sufficient amount or intensity to overcome 
 the chemical union of the serum, but when introduced insufficient 
 number to unite their digestive products, or in a condition in 
 which the individual organisms are already surrounded by their 
 ferment, they are able to attack the serum, living upon it and 
 multiplying in it. 
 
 This consideration has an important surgical relation. In this 
 view, it is not necessary that an agent acting as an antiseptic 
 should be capable of destroying the micro-organism. If it is 
 capable of neutralizing the digestive ferment produced by th^; 
 
 * Formation of Poisons by Micro-Organisms. Presley Blakistoni, 
 Son & ('o., 1884. 
 
 t Transaciions of the International Medical Congress, Loirlon, 1^81. 
 
— 10 — 
 
 attacking micro-organism, the development and multiplication ot 
 the microbe may be held in check until destroyed by the diges¬ 
 tive action of the cells of the surface of the wound invaded. 
 
 The fact that spores will live in alcohol, and afterward thrive 
 when planted in a good field, does not militate against the uselul- 
 ness of alcohol as an antiseptic, however poor a disinfectant it 
 may be. By way of reference to the alphabet of the subject, tiic 
 facts known of the nature of the poisons evolved by micro-or¬ 
 ganisms imply that by their nature and their modes of action 
 they may be arranged in three classes. 
 
 1. The local effects of a digestive fiuid by which the cells 
 attacked are paralyzed and then destroyed. When the invad¬ 
 ing organisms are circulating in the blood, they infiltrate the 
 white blood corpuscles and destroy them. A period of incuba¬ 
 tion elapses between the invasion and a sufficient multiplication 
 of the microbes to produce a manifest local disease or to affect 
 the general health. 
 
 The superior vital force of the blood or tissues may arrest or 
 destroy the invading agents. When unable to do this, the forces of 
 resistance may yet establish a wall of limitation so that there may 
 be only a local inflammation or a small abscess; and when the 
 localization is less complete, the lymphatics going from the spot 
 affected may become inflamed. 
 
 2. The production of a poisonous waste product, wliich, beij|^ 
 taken up into the circulation, poisons in analogy with morp^H 
 and strychnia, which alkaloids in this view, may be classed^* 
 alkaloid waste products of the poppy and the strychnos. ^ 
 
 The inoculation of such a poisonous waste product produces 
 immediate disease without an intervening period of incubation. 
 
 Sepsin, the waste product of septic action, when filtered out 
 from the microbes which produce it, immediate!}' produces gen¬ 
 eral disease when inoculated, though there is nothingjiving in it 
 by which it can bdi multiplied or reproduced by the processes of 
 cultivation. Thisiimpossibility of cultivation shows that the poi¬ 
 son has been separated from the vital agents which have pro¬ 
 duced it. 
 
 The entrance ofHepsin in sufficient quantity, whether gener¬ 
 ated in a wound or ji;oer, or injected artificially, destroys life, but 
 if insufficient for this, recovery takes place as in the case of other 
 poisons. 
 
 3. Pathogenic poisons areUhose of special diseases which are 
 
 / 
 

 supposoa to arise from microbes of peculiar species on one theory, 
 or on: another theory, such rs ar profoundly modified by the 
 tem])erature and the food-media with which their growth and 
 multiplication have been circumst need. 
 
 These microbes are called by Klein pathogenic to distinguish 
 them from microbes which pro-^uc only septic effects and which 
 are called septic microbes. All these pathogenic microbes have 
 a period of incubation, some lo* ger and some shorter. 
 
 During this period of incubation, the invaders are living upon 
 the tissues at the point of entrance, multiplying and extending, 
 or if floating in the blood, they are attacking the white blood 
 corpuscles in greater and greater number. According to their 
 nature they produce different dib“\8es. 
 
 Some cause a gangrene as they travel and are very local, until 
 the system becomes attacked by sc ptic poisoning from the septic 
 decomposition of whatever is destroyed, while others diffuse 
 themselves in the blood. Others, like the bacillus of tuberculosis 
 and of actinomycosis, lodge upon particular spots, multiplying 
 and destroying the tissues. 
 
 The mode of poisoning by atmospheric micro-organisms which 
 is most to be feared in surgery, is that of erysipelas, because the 
 agents of this infection are more abundant in dwelling'houses 
 and hospitals and most difficult to eradicate. The micrococcus 
 of erysipelas is extremely minuU 
 
 As quoted by Klein (j). J^S of M cTo-Organisms) Feheleiscn cul¬ 
 tivated the micrococcus of erysipelas through fourteen genera¬ 
 tions, and with the last generation produced erysipelas on the 
 ears of rabbits, and on some tumors and lu]mfl ulcers of human 
 patients, the application being nsade for the purpose of curing the 
 local diseases. 
 
 Feheleisen found thatathree percent, solution of carbolicacid 
 and a or\Q per cent, solution of mercuric bichk ride destroyed the 
 vitality of this micrococcus. 
 
 It thus appears why a spray or irrigatio of either of those 
 agents upon a wound during the progress jf its formation in 
 the course of a surgical operation, is a protection against an ery¬ 
 sipelatous contamination. 
 
 The treatment of microbes in order to destroy them or render 
 them inactive is (1) by heat not less than 150° F. (71° C), and 
 some of them require 300° F. (148° C), prolonged and repeated } 
 (2) by disinfectants which destroy the ^erms of the dangerous 
 
— 12 — 
 
 microbes, and by antiseptics which hold their development and 
 activity in check without destroying them. An interesting illus 
 tration of this distinction is given by Dr. W. J. Miller, of Dundee, 
 Scotland, in an article on contagium in the London Practitioner 
 for Sept., 1884. 
 
 Dr. Dougal suspended the action of vaccine lymph by the 
 incorporation of carbolic acid, but when, by exposure to the open 
 air, the antiseptic had evaporated the l;;j^mph was found to have 
 been preserved unimpaired. According to this and some other 
 observations ^‘Carbolic acid is not a disinfectant, not a destroyer 
 of organic matter, but rather an antiseptic or preserver of organic 
 matter, arresting and preventing putrescent and fermentive 
 change, and suspending zymotic action for a time, leaving such 
 matter unchanged after the volatilization of the antiseptic.'^ 
 
 This distinction may be criticised, by saying that a strength 
 of carbolic acid of suflScient intensity to hold back and paralyze 
 the invaders, may be weak enough not to injure the organisms, 
 to be preserved. In the case of vaccine virus, it is not injured 
 by a strength of 2^ per cent, though the putrefactive microbes arc 
 held in check. These microbes would quickly destroy the spec¬ 
 ial contagium if not opposed by this or some other antiseptic. A 
 stronger preparation of carbolic acid would destroy both inva¬ 
 ders and defenders and be a disinfectant. A strength of ^ per 
 cewf. preserves bread pulp and ^ per cent, preserves broth and milk. 
 Washing the hands in a 5 per cent, solution is thought to be the 
 weakest solution capable of protecting the hands against receiv¬ 
 ing and imparting contagium, and this is far inferior to a solution 
 of sulphurous acid. In the form of vapor, however, it is doubt¬ 
 ful whether carbolic acid has any effect whatever on account of 
 its great dilution. 
 
 All the experiments which have been made with carbolic acid 
 vapor are negative. 
 
 Among the disinfectants, Dr. Miller (above quoted) considers 
 sulphurous acid (from burning sulphur) the most valuable of all. 
 Its vapor destroys every microbe, whether zymotic, septic or 
 pathogenic. 
 
 Its gas permeates every crack in the walls of a room, and its 
 solution is easily applicable to the surfaces of solid bodies. Its 
 only objectionable feature is the difficulty of employing it in 
 rooms while people are in them. 
 
 It is not necessary here to enumerate and compare even the 
 
—13— 
 
 principal antiseptics and disinfectants. Chlorine, hydro-chloric 
 acid, iodine and bromine are powerful but difficult to manage. 
 
 Salicylic acid, boric acid, iodoform and mercuric oxides and 
 salts are excellent antiseptics for local application in the solid 
 iorm, the choice among them being determined by circum¬ 
 stance and convenience. 
 
 AIR PURIFICATION. 
 
 We come now to another method of managing the subject. 
 Taking a hint from the observations recently made in Paris, and 
 quoted in the beginning of this paper upca the effect of rainy 
 weather upon the number of microbes floating in the atmosphere, 
 it occurs to ask, whether or not it is practicable to subject the 
 air entering an operating room to the influence of artificial 
 showers in order to precipitate lo the ground the whole or the 
 greater part of these enenves of surgery. 
 
 They are known to be heavi- r than the air. because they en¬ 
 tirely disappear from the air within a tight box which has been 
 for several months in one position. This principle of rest is of 
 no use to us, for the purification of the air of an operating room 
 by this means is impracticable. 
 
 The dry filtration by means of cotton or other substances to 
 entangle and arrest the particulate substances floating in the air, is 
 not practicable on account of the rapidity necessary in the entrance 
 and exit of the air in order to displace the agents entering from 
 without during the progress of an operation, and those emanating 
 from'the occupants of the room. If, however, we can cause the 
 air entering the room to pass though several showers of water, 
 we have an expedient which may entangle these objects and carry 
 them to the ground. 
 
 The following is a description of sin 4 a 'evice. 
 
 1. Basement.— On the right hand is an entrjtnce ventilator, twenty- 
 inches in diameter, in which a stenm jet is u .ade to play in order to infil¬ 
 trate the entering air with very fine globules of vater. (2) (3) 
 
 2. The air thus moistened passes in the lire *tion of the arrows under 
 a curtain or diaphragm reaching within fifte n inches of the floor. Under 
 this curtain lies an iron pipe with numerous small holes drilled in the 
 upper side.furnishing an interrupted spray under the curtain, and making 
 it necessary for all the moving air to pass t irough this artificial shower 
 near to the floor and into the next room varme i by the stove seen on 
 the left hand of the diaphragm or screen. (3) 
 
 3. The air, thus warmed, passes through filter, composed of shelves 
 of tliin muslin through which water is dripping. The warmed air 
 
 \ 
 
—14— 
 
 
 ih’gt passes over the top of a vertical screen to avoid the entrance of 
 cold air, tlien under another vertical screen, and then back and forth 
 between hori/ontal screens fifteen inches apart, dripping with water and 
 finally through the spray which supplies this Avater. (G) 
 
 Thus there are three filtrations of the air, one by steam and two by 
 water. 
 
 4. The air thus filtered three times, emerges through an opening in 
 the floor and goes to the top of the o])erating room above. [7] 
 
 Fig. 1. 
 
 Basement below and Operating Boom a,hove — Scale, one to sixty. 
 
 5. Operating Boom. —Tlie exit ventilation is seen on the 
 opj^ osite, or right hand side of the room, in the direction of the 
 ‘arr,o‘v^''8.) Tliis is effected by a movable shaft or box, made by 
 
tacking muslin upon a frame, so that it can be set up against a 
 window, with the upper sash pulled down to the necessary degree. 
 The shaft can be shifted from one window to another to be free 
 from the pressure of the wind, or on the opposite side, or from 
 the wind. The arrangement thus far, is to get an atmosphere 
 more pure than that outside, and through the frequent change of 
 the air in the operating room, to get rid, to the greatest possible 
 degree, of the contamination of the air (during the progress of 
 an operation) by the emanations from surgeons, assistants, spec¬ 
 tators, and the patient himself. This change is secured by the 
 entrance of filtered air from the basement and the exit, from the 
 floor of the operating room, of the air which has been the longest 
 in the room, having descended gradually from the ceiling where 
 the air is hottest, after having entered from the warming cham¬ 
 ber below. 
 
 6. The floor of the operating room is made of yellow pine, 
 and filled with paraflin to as great a depth as heated smoothing 
 irons can drive it. By this means, all cracks are filled so as to 
 be non-absorbing. Under this, lies a layer of tarred paper upon 
 a cemrnon floor upon the joists. Between the joists, lies a layer 
 of tarred paper upon the ceiling, the underside of which ceiling 
 is painted, and lined with muslin while the paint is fresh. The 
 muslin is again painted on the under side. The floor thus has 
 seven layers, including the joists. 
 
 7. The operating room is free from closets where anything 
 unclean can be hidden, and all wood work is either paraffined or 
 painted. 
 
 8. There is no opening into any other room; about six feet 
 of space intervening between the door of entrance and the near¬ 
 est wall of the main building. 
 
 9. Before the use of the room for an operation involving 
 the opening of a joint or the peritoneal cavity, it is intended that 
 the rooms above and below shall be fumigated by sulphur burn¬ 
 ing in the basement. An iron pan for this purpose is figured in 
 the cut(8) resting over a Bunsen burner for the combustion of 
 sulphur. This is to be done for the destruction of any floating 
 
 I material of an organic character which may have gained en¬ 
 trance while the room may have been out of use. 
 
 It is found by trial that when the different sprays of water 
 are going, one can remain very comfortably in the room above 
 while sulphur is burning in the room below j the fumes bbing first 
 
16— 
 
 absorbed by the steam and having then to pass through the two 
 different showers of water become thoroughly percipitated. 
 
 10. This building is the execution of a theory of combining 
 the best known expedients for securing the best possible atmos¬ 
 phere for surgical operations, by excluding noxious agents and 
 by destroying or expelling those which may have stolen in, or 
 which may be introduced by the patients, or by the surgeon and 
 his assistants and guests. It is supposed that enough air will 
 enter and escape to change the whole volume of the air once in 
 fifteen minutes. The exit draft coming from the floor will carry 
 away most of the floating material. 
 
 11. The employment of a spray or douche of carbolic acid 
 of the strength of 4 to 100, or of mercuric bichloride of 1 to 10, 
 000, or other antiseptics, locally applied, though less necessary 
 than in an ordinary room, may yet be resorted to in order not 
 to omit any useful precaution. 
 
 12. The employment of solutions of carbolic acid, mercu?’ic 
 bichloride or permanganate of potash with the nail brush for 
 cleaning the hands should be supplemental to the fixed provi¬ 
 sions against septic and pathogenic particulate infection. 
 
 13. The bathing of the instruments in carbolized water, while 
 this proceeding is incapable of disinfecting or destroying any 
 germs which may adhere to them, may yet be useful in an antisep¬ 
 tic sense i, e. by destroying microbes in a developed state or free¬ 
 ing them from the supposed secretion by which they may be sur¬ 
 rounded, and which may serve as their weapon of attack by 
 which they digest or destroy the surfaces with which they come 
 directly in contact. 
 
 14. A useful precaution on the part of the operator may be 
 a bath and a change of clothing, the hair and head being dam¬ 
 pened so that dust will not escape from them; and yet another 
 precaution may be the wearing of gowns which will oblige all 
 dust escaping from the clothing of the operator and his assistants 
 to fall to the floor whence it may escape with the draft which 
 carries out the lowest stratum of the air. 
 
 Note. The construction of an opemtin^ room on the principles 
 here explained in a hospital already built, without erecting a detached 
 building, would require tl»at two rooms should be taken one above the 
 other and if the upper one can have a skylight it will be of great advan¬ 
 tage. The lower room might be in the basement with a shaft not less 
 thaif^fS) three feet in diameter extending to the upper room which might 
 be un ' -r the roof for the advantage of a skylight. All communications 
 must b^ Closed by brick and mortar and an entrance opening made in the 
 outer WHi." theapproach being secured by means of aphdform on the out¬ 
 side of the building, so that it must be unavoidable to go into the open 
 air for entraiice and exit. The lower room should be equally shut off from 
 communiation Afitli other rooms of the building. 
 
I