/*! CIS, JO C/SA'TS. 
 
 THE 
 
 PROBLEM OF MANFLIGHT 
 
 BY 
 
 JAMES M E ANS 
 
 V*2fef 
 
 THE FLIGHT OF OTTO LILIENTHAL, OF STEGL1TZ, PRUSSIA, AS ACTUALLY 
 
 ACCOMPLISHED IN 1893. ACCURATELY DRAWN FROM 
 
 AN INSTANTANEOUS PHOTOGRAPH. 
 
 BOSTON, MASS. : 
 
 W. B. CLARK E & CO., 
 
 340 WASHINGTON STREET. 
 
 1894. 
 

THE PROBLEM 
 
 MANFLIGHT. 
 
 BY 
 
 JAMES MEANS, 
 
 This pamphlet will be sent, postpaid, to any 
 address on receipt of ten cents in stamps. 
 
 BOSTON, MASS. : 
 W. B. CLARKE & CO., 
 
 340 WASHINGTON ST. 
 1894. 
 
 >?"% 
 
 
Copyright, 1894, 
 * Jf V " J A M E<S .' & fi it if S. 
 
 0rftJell antj 
 
 BOSTON 
 
- 
 
 ' 
 
 THE PROBLEM OF MANFLIGHT, 
 
 As the century draws to its close the interest in the 
 subject of aeronautics steadily increases. There already 
 exists a keen curiosity to know what the aerial machine 
 of the future is likely to resemble, and also to know 
 whether the nineteenth or the twentieth century will 
 claim it for its own. 
 
 In the present article the writer wishes to show what 
 inferences may be drawn from the laws of nature as so 
 far ascertained by observation and experiment, and he 
 wishes also to point out a way which may lead to 
 further progress. 
 
 The investigators of this subject are now divided into 
 two camps : on the one side there are men who, like 
 Mr. Maxim, are endeavoring to construct machines 
 which will carry motors and therefore be self-propel- 
 ling ; on the other side there are men like Mr. A. M. 
 Wellington, who maintains that a motor is unnecessary 
 and that wind-power is sufficient. 
 
 In the New York Engineering News, of Oct. 12^ 
 1893, Mr. Wellington, in a very interesting article en- 
 titled w The Mechanics of Flight," makes the following 
 statement : "If the conclusions so far reached in this 
 paper be accepted, it is obvious that they greatly 
 simplify the problem of artificial flight by reducing to a 
 minimum the demand for power, making it chiefly 
 necessary for acquiring the first initial velocity. All 
 attempts at aviation which include any motor for pro- 
 
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4 THE PROBLEM OF MANFLIGHT. 
 
 pulsion are, in my judgment, on wrong lines, and pre- 
 destined to certain failure, since they not only neglect, 
 but destroy, the action of the forces by which true flight 
 may be and is attained. I will not go so far as to say 
 that some (soaring) birds, in the exuberance of power, 
 may not use the wings to accelerate, as they do to retard 
 motion. I think they do, but only in an abnormal way ; 
 it is wholly unnecessary, and even destructive of all 
 normal flight. The fish needs a propeller, because it 
 has no gravity in water; the bird does not need it, 
 because it has gravity, and in that gravity has the best 
 and smoothest of all conceivable means of propulsion, if 
 he can make the wind lift him uphill whenever he has 
 slid far enough downhill. If so, man commits an ab- 
 surdity when he flies in the face of nature and assumes 
 a propelling force where none is needed or exists." 
 
 Later on in this article, I wish to describe an instru- 
 ment, experiments with which can be made to answer 
 for us the question as to whether or not a motor is 
 needed; but just here further quotations should be given 
 to show the trend of the best thought. 
 
 Aeronautics (N.Y.) for January contains Professor 
 Langley's remarkable paper entitled ' :c The Internal 
 Work of the Wind." The closing paragraph is as 
 follows : 
 
 w The final application of these principles to the art 
 of aerodromics seems, then, to be, that while it is not 
 likely that the perfected aerodrome (air-runner) will 
 ever be able to dispense altogether with the ability to 
 rely at intervals on some internal source of power, it 
 will not be indispensable that this aerodrome of the 
 future shall, in order to go any distance even to cir- 
 cumnavigate the globe without alighting, need to carry 
 a weight of fuel which would enable it to perform this 
 
THE PROBLEM OF MANFLIGHT. 5 
 
 journey under conditions analogous to those of a steam- 
 ship, but that the fuel and weight need only be such as 
 to enable it to take care of itself in exceptional moments 
 of calm." 
 
 Mr. Octave Chanute, in his admirable chronicle en- 
 titled " Progress in Flying-Machines," which will soon 
 be published, says in one of his closing chapters: w But 
 it is possible to utilize a still lighter power [than that 
 of engines], for we have seen that the wind may be 
 availed of under favorable circumstances, and that it 
 will furnish an extraneous motor which costs nothing 
 and imposes no weight upon the apparatus. 
 
 :<r Just how much power can be thus utilized cannot 
 well be told in advance of experiment; but we have 
 calculated that under certain supposed conditions it 
 may be as much as some six-horse power for an aero- 
 plane with one thousand square feet of sustaining 
 surface ; and we have also seen that while but few ex- 
 perimenters have resorted to the wind as a motor, those 
 few have accomplished remarkable results." 
 
 The indications seem to be that we must try to con- 
 struct a machine analogous to the sailing-yacht rather 
 than to the steamship, though perhaps the aerial machine 
 of the future will be, so far as power is concerned, 
 analogous to the yacht Sunbeam with its auxiliary 
 screw. 
 
 Before continuing further with this subject, I wish to 
 call attention to certain facts concerning the storage of 
 power and the flight of soaring birds. First, in regard 
 to the storage of power. It is well known that the con- 
 struction of a useful electric storage-battery presents a 
 most difficult problem. Such a storage device is needed 
 for use upon the surface of the earth; yet, for purposes 
 of aerial navigation, there is a much simpler accumulator 
 
6 THE PROBLEM OF MANFLIGHT. 
 
 which can be used. Take, for example, one hundred 
 pounds of lead and let energy be stored in it by giving 
 it altitude, just as energy is stored in the weight of a 
 clock when it is wound. 
 
 What is known as one-horse power is the amount of 
 energy which must be exerted in lifting thirty-three 
 thousand pounds at the rate of one foot per minute, or 
 five hundred and fifty pounds at the rate of one foot per 
 second, or fifty-five pounds at the rate of ten feet per 
 second. To give an illustration, it may be stated that if 
 a man weighing one hundred and sixty-five pounds 
 ascends a flight of steps ten feet high in three seconds, 
 he exerts for the time being just one standard horse- 
 power. 
 
 A small balloon which can lift one hundred pounds 
 of lead three hundred and thirty feet high in one minute 
 exerts one-horse power. 
 
 The lead when lifted to this height has stored within 
 itself thirty-three thousand foot-pounds of energy. 
 
 Now, if weights can be made to slide downhill upon 
 aeroplanes at very gentle grades, then the balloon be- 
 comes a valuable motor which stores energy in its load 
 by giving it altitude, and the weight lifted becomes a 
 reservoir of the very power needed for its own trans- 
 portation, and the name of Montgolfier, the inventor of 
 the under-estimated balloon, takes its place as that of the 
 real founder of the useful art of aerial transportation. 
 
 Whether or not it is possible to transport freight by 
 sliding it down long and gentle inclines by means of 
 aeroplanes will be considered further on; just here we 
 must consider the soaring power of birds. 
 
 In w The Reign of Law," by the Duke of Argyll (first 
 published in 1867), there is a most notable chapter in 
 which the flight of birds is analyzed. In a note the 
 
THE PROBLEM OF MANFLIGHT. 7 
 
 author makes the following statement: w I owe to my 
 father [John, seventh Duke of Argyll] my knowledge of 
 the theory of flight, which is expounded in this chapter. 
 The retired life he led, and the dislike he had of the 
 work of literary composition, confined the knowledge 
 of his views within a comparatively narrow circle. But 
 his love of mechanical science, and his study of the 
 problem during many years of investigation and experi- 
 ment, made him thoroughly master of the subject." 
 
 Every student of the subject of flight should read the 
 interesting work just mentioned. We may not agree 
 with all the conclusions which are reached, yet the 
 author gives most stimulating food for thought. 
 
 The following paragraphs are among the most strik- 
 ing, showing, as they do, advanced ideas: 
 
 w In the first place, it is remarkable that the force 
 which seems so adverse the force of gravitation 
 drawing down all bodies to the earth is the very force 
 which is the principal one concerned in flight, and with- 
 out which flight would be impossible. It is curious how 
 completely this has been forgotten in almost all human 
 attempts to navigate the air. Birds are not lighter than 
 the air, but immensely heavier. If they were lighter 
 than the air they might float, but they could not fly 
 This is the difference between a bird and a balloon." (p. 
 130, Am. ed.) 
 
 " No bird is ever for an instant of time lighter than 
 the air in which it flies ; but being, on the contrary, 
 always greatly heavier, it keeps possession of a force 
 capable of supplying momentum, and therefore capable 
 of overcoming any lesser force, such as the ordinary 
 resistance of the atmosphere, and even heavy gales of 
 wind. The force of gravitation, therefore, is used in 
 
8 THE PROBLEM OF MANFLIGHT. 
 
 the flight of birds as one of the most essential of the 
 forces which are available for the accomplishment of the 
 end in view." (p. 131.) 
 
 " The lightness of a bird is a limit to its velocity. 
 The heavier a bird is, the greater is its possible velocity 
 of flight because the greater is the store of force ; 
 or, to use the language of modern physics, the greater is 
 the quantity of ' potential energy ' which, with proper 
 implements to act upon aerial resistance, it can always 
 convert into upward, or horizontal, or downward motion, 
 according to its own management and desires." (p. 
 144.) 
 
 " When a strong current of air strikes against the 
 wings of a bird, the same sustaining effect is produced 
 as when the wing strikes against the air. Consequently 
 birds with very long wings have this great advantage, 
 that, with pre-acquired momentum, they can often for 
 a long time fly without flapping their wings at all. 
 Under these circumstances a bird is sustained very 
 much as a boy's kite is sustained in the air. The string 
 which the boy holds, and by which he pulls the kite 
 downwards with a certain force, performs for the kite 
 the same offices which its own weight and balance and 
 momentum perform for the bird. The great long- 
 winged oceanic birds often appear to float rather than 
 to fly. The stronger is the gale, their flight, though less 
 rapid, is all the more easy, so easy indeed as to appear 
 buoyant ; because the blasts which strike against their 
 wings are enough to sustain the bird with comparatively 
 little exertion of its own, except that of holding the 
 wing vanes stretched and exposed at proper angles to 
 the wind. And whenever the onward force previously 
 
THE PROBLEM OF MANFLIGHT. 9 
 
 acquired by flapping becomes at length exhausted, and 
 the ceaseless, inexorable force of gravity is beginning 
 to overcome it, the bird again rises by a few easy and 
 gentle half-strokes of the wing. Very often the same 
 effect is produced by allowing the force of gravity to 
 act, and when the downward momentum has brought 
 the bird close to the ground or to the sea, that force is 
 .again converted into an ascending impetus by a change 
 in the angle at which the wing is exposed to the wind." 
 (p. 152.) 
 
 It is to be regretted that the limits of this article pre- 
 vent more extended quotations from this remarkable 
 book. 
 
 Now let us recall what we have seen at sea. 
 
 When one stands on the after-deck of a steamer in 
 crossing the ocean, he may watch the soaring gulls to 
 his heart's content. When the ship struggles painfully 
 to force her way into the teeth of a gale, the birds make 
 sport for themselves they rise and dip, thus conquering 
 the wind. How? Simply by tacking; in one sense, 
 just as a yacht tacks to windward. Neither bird nor 
 yacht can sail into the eye of the wind by the wind's 
 power, but either can, by use of that power, reach an 
 objective point lying to windward. 
 
 But here the reader may say that the parallelism be- 
 tween the bird and the sailing craft is not " correctly 
 drawn, because the yacht has a keel immersed in a 
 dense medium which resists and prevents the making 
 of leeway. 
 
 Yet the soaring bird has something which, at neces- 
 sary times, holds it against the wind just as effectually 
 as the keel holds the yacht: that something is momen- 
 tum, which, while it lasts, holds the bird against the 
 wind as firmly as the kite-string holds the boy's kite. 
 
10 
 
 THE PROBLEM OF MANFLIGHT. 
 
 In Fig. i, let S represent a steamship going east- 
 ward at the rate of twenty miles per hour; W the 
 
 wind blowing westward at the rate of twenty miles per 
 hour; A a gull near the water's surface, with mo- 
 mentum which for the instant gives him an eastward 
 velocity of twenty miles per hour. While the bird's 
 momentum lasts it holds him firmly against the wind. 
 At the point A the bird inclines his wings so that the 
 wind strikes them on the under side, and he is lifted and 
 lifted until, at the point B, his momentum is so reduced 
 that he must tack; then he gives to the wind the thin 
 edge of his wings and slides down to the point C, and 
 then, with velocity regained, he repeats the manoeuvre. 
 Altitude sacrificed becomes velocity or momentum, and 
 momentum sacrificed becomes altitude. In this de- 
 scription of the gull's soaring to windward, the move- 
 ment is reduced to its simplest elements, and it leaves 
 out of account the graceful sinuosity of the bird's airy 
 travels, just as the teacher of dancing leaves grace out 
 of account when she teaches the beginner the elements 
 of the steps. 
 
 What has here been said about the storage of energy 
 in weights, and concerning the elements of flight, is all 
 intended to lead up to the important subject of sliding 
 
THE PROBLEM OF MANFLIGHT. 
 
 II 
 
 freight downhill upon aeroplanes. It may be asked, 
 How about a calm? 
 
 There is no calm for the aeroplane. Give it altitude 
 and it can gain velocity, and velocity gives the 'wind 
 
 f flight- 
 
 The plan for the transportation of freight is simply 
 
 this: at each shipping-point a power-house (D, Fig. 2) 
 
 fff HOUR 
 
 Fig. 2. 
 
 may be established to operate captive balloons. These 
 should be cellular, and should be made to hold gas 
 with little waste. In its action the apparatus would be 
 what might be called an inverted elevator; that is, the 
 steam or water-motor in the power-house would not 
 hoist the freight, but, instead, would pull the balloon 
 down after it had hoisted the freight and discharged 
 it by means of a soaring machine, which will presently 
 be described. 
 
12 THE PROBLEM OF MANFLIGHT. 
 
 In Fig. 2 A represents a captive balloon at a height 
 of one thousand feet. B and C represent the courses 
 which would be taken by dirigible aeroplanes or soar- 
 ing machines bearing loads of freight. 
 
 Perhaps this seems fanciful. Then let it be remem- 
 bered that the feat of safely sliding down a long and 
 gentle incline upon an aeroplane has already been per- 
 formed by Otto Lilienthal, of Steglitz, Prussia. His 
 experiments were illustrated and described in the Berlin 
 Illustrirte Zeitung of Oct. 7, 1893, and one of the draw- 
 ings all of which were correctly made from instan- 
 taneous photographs is here reproduced on the first 
 page of cover. An improvement upon Lilienthal's 
 device may be made by adding a pendulum. * 
 
 Now, in order to travel long" distances in the air 
 it is only necessary to improve the dirigibility of the 
 aeroplane so that the angle of descent can be brought 
 to a minimum. 
 
 How can this be done? By making repeated ex- 
 periments with very simple and inexpensive mechan- 
 ical contrivances called soaring machines, these to be 
 dropped from a height. 
 
 In Fig. 2 it will be noticed that the course marked B 
 indicates a speed of twenty-five miles per hour, that 
 marked C a speed of one hundred miles per hour. 
 
 What speed may we expect of an improved soaring- 
 machine? and upon how gentle a decline can we hope 
 to see it maintain its initial velocity? First, note the 
 fact that with a dirigible aeroplane or soaring machine 
 the rate of speed is practically a matter of choice and 
 depends at the start upon the length of the first swoop. 
 The limit of speed will probably be decided by the 
 
 * See U. S. Letters Pat. No. 376937. 
 
THE PROBLEM OF MANFLIGHT. 13 
 
 strength of the machine and the breathing requirements 
 of the aerial pilot. Let us consider a railroad train. 
 Man has safely travelled at a rate of one hundred and 
 twelve miles per hour. On May n, 1893, the Empire 
 State express on the N.Y.C. R.R. reached that speed 
 in a mile run in thirty-two seconds, one mile westward 
 from Crittenden. So we know that man can safely 
 breathe when travelling at over one hundred miles per 
 hour; yet for this, of course, he needs the same protec- 
 tion which a cab gives to the locomotive engineer. 
 
 We will answer as well as we may the second ques- 
 tion, Upon how gentle a decline may we hope to see an 
 aerial machine maintain its initial velocity? When a 
 railway car is at rest upon a smooth steel track having 
 a down grade of one and twenty-three one-hundredths 
 feet in every one hundred feet, it will remain at rest if 
 undisturbed; but let it be once started downward by 
 ever so slight an impulse and it will run down the track, 
 gaining velocity to the end of the grade. It encounters 
 the head resistance of the air and the friction of the 
 track, but an aerial machine would encounter only air- 
 resistance ; is it not, therefore, reasonable to suppose that 
 a dirigible aeroplane would in a calm, maintain its initial 
 velocity while running upon a down grade of air of one 
 foot in every one hundred feet? If so, an altitude of 
 ten or twelve hundred feet would send a soaring ma- 
 chine eighteen or twenty miles, and greater altitudes 
 would give longer flights, if, as may be supposed, the 
 rarefaction of the air can be offset by an increase of 
 velocity. These are surmises, but the way to learn is 
 to experiment with soaring machines. 
 
 It is above all things important that a soaring machine 
 should, when desired, automatically keep itself in a 
 horizontal or slightly descending course. I have this 
 
14 THE PROBLEM OF MANFLIGHT. 
 
 winter begun a series of experiments with soaring 
 machines, and when these are finished the full details 
 will be reported. 
 
 In November, 1893, I launched several of these 
 machines from the balcony of the tower of Boston 
 Light, and more recently I have experimented from the 
 top of the cliffs at Manomet. The former place is an 
 ideal one for the purpose of experiment, being as it is, 
 one hundred and eleven feet above the sea with a straight 
 drop of seventy or eighty feet. Unfortunately, a gale of 
 wind was blowing when I visited the light, and two out 
 of the three machines were total failures, being badly 
 bent by the wind before they were launched. The third 
 machine righted itself before reaching the ground, but 
 the pendulum, which will presently be described, was 
 too light to do efficient work. 
 
 The experiments from the cliffs at Manomet were even 
 less successful, owing to the fact that the descent is not 
 sheer. All of the machines failed to gain sufficient 
 velocity to clear the cliff. 
 
 Those who wish to experiment with machines weigh- 
 ing only a few pounds will probably find that a height 
 of seventy or eighty feet will be sufficient if the position 
 gives a straight drop. When it comes to experimenting 
 with a soaring machine as large as LilienthaPs and carry- 
 ing a weight representing that of a man, the summit of 
 Mt. Willard, near the Crawford House, N.H., will be 
 found an excellent place. 
 
 To any one who desires to take up this most fascinat- 
 ing study, Figs. 3 and 4 will give a general idea as to the 
 construction of his first instrument for making experi- 
 ments. A represents a backbone five-eighths of an 
 inch square and four feet long, made of pine wood; 
 B, the main aeroplane, eight inches wide and three feet 
 
THE PROBLEM OF MANFLIGHT. 17 
 
 long. This should be made of light tin plate, and bent 
 in the middle so as to form a flattened V; the angle 
 should be about one hundred and seventy degrees. 
 C represents a steering aeroplane six inches by twenty- 
 four inches, pivoted at cc, also made of light tin plate; 
 D, a vertical aeroplane four inches by twenty inches, 
 rigidly fixed in the wooden backbone; E, a rod of 
 steel wire, eighteen or twenty inches long, and carrying 
 an adjustable leaden weight of three ounces; K, a rod 
 two and one-half inches long, soldered in the centre of 
 and vertical to the plane C, with a pivot at the upper 
 end with which the rod MM is connected. This rod 
 should have five or six pivot-holes at its forward end N, 
 so that its working length may be varied for different 
 experiments; J, a rod pivoted at G, free to swing fore 
 and aft; N, a pivot where the rod MM joins the rod J; 
 F, a leaden weight adjustable higher or lower upon the 
 rod J; its proper weight is x, an unknown quantity. 
 Upon ascertaining by repeated experiment the right 
 'weight for F, the right position for the adjustable 
 weight E, and the right length for the rod MM, the reach- 
 ing of the maximum efficiency of a system of aeroplanes 
 largely depends. I think that this sets forth with clear- 
 ness the problem as it stands to-day. When it is fully 
 solved and it certainly seems solvable right and left 
 steering will be a less difficult matter, and alighting 
 will be accomplished by killing the momentum when 
 near the ground by an abrupt upward slant of the main 
 aeroplanes; but this is an anticipation and a digression. 
 Now to return to the instrument we are considering: 
 
 o 
 
 this soaring machine is intended to gain velocity by a 
 swoop, and then automatically steer itself into a hori- 
 zontal or very slightly descending course, as indicated 
 by B and C in Fig. 2. It depends upon the principle 
 
1 8 THE PROBLEM OF MANFLIGHT. 
 
 that the pendulum rod always seeks the perpendicular; 
 for instance, when the machine is launched pointing 
 steeply downward, the positions of the pendulum and 
 aeroplanes are as shown in Fig. 5 ; therefore the steer- 
 ing aeroplane C will, as soon as velocity is gained, lay 
 
 F.6 7 
 
 a strong hold upon the wind of flight, and have a ten- 
 dency to bring the machine into a horizontal course. 
 Now, if the length of the rod MM is made correct by 
 adjustment at the pivot-holes near N, when the desired 
 course, a very gentle decline, is reached, both aero- 
 planes will be approximately horizontal, as shown in 
 Fig. 6. If, however, the machine deviates either 
 upward or downward from its intended course, the 
 weight at the end of the pendulum causes the steering 
 aeroplane to correct the error. Fig. 7 shows the 
 effect of a slight upward deviation. 
 
 H represents a long and very slender air-recepta- 
 cle made of thin rubber and inflated; this should be 
 pointed at both ends. It may be used to keep the 
 machine afloat when experiments are made near the 
 water. I have not yet used this, but have allowed my 
 machines to go to pieces. The design here given calls 
 for aeroplanes as being more easily made than aero- 
 curves modelled after the wings of birds, but in all 
 probability the latter will eventually displace the former. 
 
 We are brought now, after this consideration of the 
 greatest mechanical problem of the age, to ask, What 
 
THE PROBLEM OF MANFLIGHT. 19 
 
 shall be done to bring to our own century the credit 
 and honor of reaching the solution? 
 
 The answer is, encourage experiments with soaring 
 machines. Have regattas and large prizes. Appeal to 
 the people's love of sport, and show what possibilities 
 of recreation have been suggested by the experiments 
 of Otto Lilienthal. Tobogganing on ice we can have 
 only a few weeks in the year: tobogganing on air is 
 possible at all seasons. When we have made our aero- 
 planes or aerocurves automatic in their steering action, 
 flights like Lilienthal's will be, to say the least, no 
 more dangerous than football and quite as interesting. 
 
 In order to encourage the designing and construction 
 of soaring machines, I suggest that a sum of money be 
 raised to be offered as a prize to the constructor of the 
 most successful soaring-machine, the award to be made 
 after a public trial of the same, to take place early in 
 September of the present year (1894). 
 
 I will subscribe one hundred dollars if others will 
 subscribe, in any sums they choose, nine hundred dol- 
 lars more, to make a purse of one thousand dollars, 
 provided that the publisher of some journal oi wide 
 influence will be custodian of the fund. 
 
 One or two more thoughts in conclusion. We have 
 seen how the soaring bird tacks, first up, then down, 
 then up again, and then down again. That conveys the 
 idea of the perfection of rapid transit for passengers 
 and freight. With the captive balloon we can tack up, 
 with the soaring machine we can tack down. Short 
 tacks up, long tacks down; there is no calm for the 
 aeroplane; give it altitude and it can seize from the 
 calm the wind of flight. 
 
 Imagine a bowling alley four hundred feet long, per- 
 fectly level, with an athlete at one end and a boy at the 
 
 ' 
 
20 THE PROBLEM OF MANFLIGHT. 
 
 other. Let the chute which returns the balls have a 
 drop of fifteen inches in every, one hundred feet; im- 
 agine the game to be one of rapid transit instead of ten- 
 pins. It is P competition between the two ends of the 
 ajley to see which end can make the most of what 
 energy it has. Let the athlete exert all his strength 
 to propel the spheres ; see them arrive at the end of the 
 alley after their journey of four hundred feet, with 
 sluggish speed; the boy lifts them to a height of five 
 feet to the chute, gives them a gentle push, and they are 
 returned to the athlete's end, arriving, not as sluggards, 
 but as filled with energy. A short tack up and a long 
 tack down is what does it. 
 
 There you have the old and the new methods of transit 
 represented. The athlete represents the steam loco- 
 motive which, with all its polish and glitter, wastes 
 energy. The boy represents the balloon, the lifter, 
 which stores energy in matter by giving it altitude. 
 The chute represents the free highway which through 
 all the centuries men have supposed to be lacking. 
 
 Aerial transit will be accomplished because the air 
 is a solid if you hit it hard enough. 
 
 James Means. 
 
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