On the various modes of flight in relation to aeronautics / by James Bell Pettigrew.

Date:
[1867]
Catalogue details

Licence: Public Domain Mark

Credit: On the various modes of flight in relation to aeronautics / by James Bell Pettigrew. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    ~~C -=-='■?——- i^oijal l^ustitutiou of (*F;veat liritain. WEEKLY EVENING MEETING, Friday, March 22, 1867. Sm Hknry Holland, M.D. D.C.L. F.R.S. President, in the Chair. Dr. James Bell Pettigrew, M.D. Edin. ASSISTAN'T CURATOR OP THE EOTAL COLLEGE OP SURGEONS OP ENGLAND MUSEUM. Oh (he Various Modes of Flight in relation to Aeronautics. The snbject of flight, natural and artificial, is ono which has occupied the attention of mankind from a very early period. It involves a more or less intimate acquaintance with Anatomy, Physiology, Mechanics, and the higher branches of Mathematics. If regarded as a natural movement, it forms one of the thi'ee kinds of locomotion by which animals progress—the remaining two being walking and swimming ; if regai’ded as an artificial one, it repre- sents the imsolved problem of that grand trio which has for its integi’al parts the locomotive, steamboat, and flying machine. Had time per- mitted, it was my intention to have gone into the subject of locomotion at length. I find, however, I must cm-tail my remarks under this head, which I do with reluctance, from a feeling that the chain of animal movements, like the great chain of existence, winds in and out and doubles upon itself so completely, as to render a partial examina- tion of it in many respects unsatisfactory. The movements of animals are adapted either to the earth, the water, or the air. There are others, however, of a mixed character, where they are suited equally to the land and water, or even to the land, water, and air. The instruments by which locomotion is attained are therefore specially modified. This is necessary because of the difiereut densities and the different degrees of resistance furnished by the land, water, and air resj)cc- tively. ■ As the earth affords a greater amount of support than the water, and the water than the air, it requires a greater degree of muscular exertion to swim than to walk, anti a still greater one to fly. B