Show and Studies About Them Under and d T I I U dIU an U the Smithsonian Institution I I i i s o g I i I I II j TL n I i t i I i J j I Buzzards Buzz in Flight I V hat is the secret of the flight of birds bud ani insects How Hm much of this thisbe be seen fl r I t an can be discovered and applied to the ih radical practical use of inn To answer th questions iu from thoroughly observations b is the ultimate object f a s series ries of investigations by Dr von vonIe l Ie of the Zoological institute Pra ne conductor under a grant from I th Smithsonian Institute at Washing mi WI Mutinies sustained by gases j luitT light r than air have ha been found un 1 util and impracticable If man is Iscer MI r i in to lit he I carried through the atmos it is now generally conceded that ho hI must be by b the application of some si principle Involved in the flight nf of birds and insects t Hi von on researches ex ox f HUng aver voi a period of about six I years have brought to light fitall mur III tot in facts so full of possibilities pos i i hat chat the tho secretary of the Smithsonian Institute has just signed a further r I grant rant to enable a continuance of the I I rk I I ho he fund from which these grants grant I ar are made mad was established in 1891 by Thomas ThuI as i George rge e Hodgkins of Setauket I v S V T 00 the income from one ones s half of which is devoted to the in I reuse rease r as and ani of more exact knowledge know dge in regard re rd to the nature and r properties of atmospheric air in con eon connet I net nt tion with the welfare of man The i object t of f the fund has lias been interpreted broa broadly H To discover the secret of the flight of birds bird and insects is a purpose to which ilich a portion fIt of the income of the Hodgkins fund has been devoted It is in nn object touching dire tI upon up n hu Im Imn hunI n iiii nI S The fund therefore 1 r ads i N 1 mat material rial support to experiments huh ma may Hlay mean mu the ultimate exten si i M o of f mans control over an element hitherto unconquered Th The resent I ent grant to Dr von yon Lendt Len dt is for the special purpose e as S secretary Walcott says to make a and exact investigation of the resins raus of flight of the best belt represent atie fixers r t yens ers of the insect orders In Inthis Int Inthis this his t investigation inv the wings of insects i re rc to be considered in their relation i to i the mechanics of flight as well ell as from torn rom a purely morphological point of ofie view jew ie This research re ear h follows naturally upon conclusions which Dr von yon Len Lend Leni d has hu already alread reached In work i conducted personally persona H and under his dl di I rf Un n for a number of ot years ear Two ports imports hae have been published by the Smithsonian Institute and ami two more are ar aI now in press to appear as regular issues of the thc Smithsonian miscellaneous Dr von xon nn first work un under der rte 1 r a Smithsonian grant was per in 1100 1400 In consisted mainly of ril studies into the structure and functions of the organs of flying fi crea erea lurs tU tur 1 as ae a R preparation suitable for re reMatches Matches into the actual mechanics of eight Alight Shwe Since then much of his time has lias bw been en taken up in personal labora laboratory tory lOry Investigations or in directing in of his pupils in the uni university Y p ity at Prague The first set t of experiments completed ed d 1 about three years ago o brought out some mp facts concerning the theu u of birds In Jn relation to the weight of If th their ir lr bodies It was established be ht vond y 1 a doubt that some property of air enabled larger and heavier lH avier birds such as the albatross and the eagle to sus sustain sustain tain their weight with comparatively much smaller wing surface It was worked out by analogy analog that given the secret of control o of 01 motion a man weighing DO pounds 90 kilograms could sail aU through the air with a sus SUl sustaining sustaining wing surface of about three square re yards 27 7 square meters But when wh R Dr von yon L turned to consider the actual mechanics of he was confronted immediately t n by y the fact Met that all an birds by no means mean fy ny alike In Met f ct there th re could hardly IK he 11 established he 1 a R mean similarity between be 00 between tween n all ail he to varieties From the great oaring soaring a truss and sea eagle which may nav sail san for or half an hour without the quiver of a feather to the whirring sparrow andt a the tho buzzing humming hummingbird bird which rot roty ty solely for support upon the rapid motion of their wings there is ii a long line iilA liri of flyers These two ex exT T remes tho t albatross and the humming the experimenter took as types Insects also ateo he found to be classed in Ina a like manner Among both Melts birds and insects how liow howver however ver ever the were found not to be ber restricted r to the large creatures and the flappers to the small On the tho contrary con contrary cont t th Mare re were creatures of all si 81 In i i p In the faller class themon th emon butterfly butte was placed beside Ide t tork and the silver gull beide de the dragon fly The flapper apper dais claa embraced liters flyers tI ers from the bust bustard ard arI ar and the pheasant to the house fly and the gnat In this study of flight method therefore the question of size ht hato h d to be eliminated Muscular Ji power was an element to tob tobe tobe b be considered Ci Dr von yon was that the flappers were gifted much stronger muscles than the 1 U rs And merely for Illustrative 1 for he does not as yet con cond condar dar Ider d r the feasibility ft of actually attach tg C wings to man he found that al alt t ugh tough a human being could not Imme C develop enough muscle to join f of flopping flyers he ho might T 1 J 1 l be able if he knew how to soar III DI DIAl Al a I these conclusions c hinged upon the Casting asting phenomenon that the Int In InIe t fe re in weight wel ht to be carried through fir Is not proportional to the uc lu tic ry increase in size of the support r f g surface that is the tho larger the bird birdt t smaller mailer in proportion are the wings I 1 results can be explained only fc r t the supposition that the resist r 3 s of the air against moving wings is P directly proportional to their size t tu it j that in enlarging the wings the ther r power of q t the air ir lr against them Ses in a greater reater gr their superficial dimensions Knowing Itri ll that t i air requires an appreciable time to 11 d to the tho pressure of the moving Wing g the tho larger the wing surface the greater the tho quantity of air all displaced add the greater the resistance of or compressed air to the subsequent wins wing stroke must ant afat a tup upon n It Jt it is evident eId nt that Ul t this conclusion Is correct I i I Upon the principle of compressed compre ed air airI therefore th may rest lest the ultimate solution solution solution tion of mens light flight above aboe the earth I At 1 the same time that Dr von on Len denfeld was vas working out these facts Dr E K studying stud under Ills his di direction direction direction at the Institute was determining ing what magic there might be in ht the feather structure of birds wings His results show how perfect for its pur purpose purpose purpose pose is the lapping of the feather quills one over another The happy combination tion of strength and lightness so 50 vivid vividly vividly vividly ly pictured In this flexible structure is la isa a combination the value of which is ismore Ismore ismore more widely realized in commercial construction every day On the under underside underside underside side and at the ends of the feather fibers Dr Maselia points out ut micro microscopic microscopic microscopic hooks which serve perve to attach easily one feather to another to make makeup up one whole wing structure Tapering Taper Tapering TaperIng ing with greater and greater flexibility toward the back and ends of the wings these feathers make possible the peculiar pe peculiar peculiar culiar action of the wing upon the air Two other sets of researches hes have just been completed under the direction direction direction tion of Dr von on The first d by Dr Bruno Muller was designed to determine the use of cor certain certain tain empty spaces In the bodies of birds which have puzzled investigators Investigator for many man years The second has haf to do with the flight of insects The air s sac ac investigation is just reported re reported reported ported to the th Smithsonian Theories filling pamphlets have in times past been launched upon the scientific world to account for these theRe cavities near the lungs and under the skin of birds Rea Rca Reasons Reasons sons ons which would preclude the possibility possibility possibility of mans mens ever navigating in the atmosphere were in ht many man cases put forth The fertility of the minds of researchers in giving s ing these spaces some function is convincing con evidence to show how at a loss less they the have been for any definite proof The little air sacs have hac been assigned two sepa separate sepa separate separate rate functions to help raise the feath feathers ers and to preserve bodily heat To the empty empl spaces near the lungs how however however however ever have been attributed powers even more wonderful It has been said that they th s 8 serve re organs for producing certain tones that they the per por perform perform form respiratory functions that they help reduce the specific gravity of the body bod that they the act similar to t a baro barometer barometer barometer meter in determining height that they the aid in fixing the wings in an extended position that they assist the digestion that they the Insure equilibrium in flight and that they ars ara store houses for air respiration for Mr lIr Muller has consid considered considered considered ered all these theories Nevertheless he reaches a very simple conclusion He Ht says I do not consider the air sac system as a whole as a collection of organs having special pelal functions but rather a system of empty Its value lies In its vacuity that is in Its containing nothing that can offer a great reat resistance or that has notable w weight eight ht Flying Is the th most complete kind of locomotion IlC moton and as such presupposes oses a high degree of bodily efficiency Our most effective machines are by no means those thole which are compact anti and solid but those composed of parts that arc aa as strong as possible and arranged arran ed edin in ht the moet most appropriate manner the being taken up by b air There is apparently nothing therefore there therefore therefore fore In the air hair sac system in birc birds s which should prevent the construction of a flying machine upon similar prin principles principles The findings in the second report just received are equally vital to the problem problem problem lem of mechanical flight Dr Lee Walter another of Dr von yon Lenden felds assistants has been examining the workings of the flying apparatus of insects The Tho stroke says Dr Walter Valter is a curious one It ItIs Itis Is Ig like a figure 6 with a small upper loon a stroke which might be reproduced reproduced reproduced mechanically A careful study has been concluded of the method by which the hind wings are attached to the fore wings since the strength of the stroke seems to come from the wings In some insects a curious set of tiny on the upper side of the back wing reach Into a little band of hair and join to scales on the under underside underside side of the fore wing making the two wings practically one In others a se cc series series ries of hooks on the upper lock with a corresponding series on the lower Just what principles of nature brought out In these researches may be applied to practical use In the flying machine taking the word literally Is yet to be determined The complete discovery however of the secret of tf suspension and locomotion involved In Inthe inthe inthe the flight of birds and Insects Is the first step In the solution of mechanical navigation in the air The theory once established beyond a doubt engineers may incorporate all practical features into IntI the construction of a machine The object of Dr von yon work under the Hodgkins grants of the Smithsonian Institution is to find facts unon u on which firmly to base a theory |