268 Proposal of an Apparatus for Flying 
Of x” +6x! +2lat........(4u?—5n), 
Jetl xn nr m 
as Fa (x —1)+ vv +3v—2vr —8n—v(4n2+38n+2) 
2 
—_——————— 
Of a-'+-6a-? + 182-3 4+ 40a-+......4(m3 +n) x-, 
=i 
SFT? (pme) fot o—3(n-fl)e — — (8n?-+11n-+104 v(n3-+4n2- 5n-2))% 
uv 
ps. 
The investigation of the foregoing series could not well be 
given here, either wholly or in an abridged state, as that would 
necessarily occupy much too considerable space, though it may be 
remarked that the method adopted and followed is very compre- 
hensive and general in its application. I am, sir, 
Your very obedient humble servant, 
Aske Terrace. ° JaMEs B. BENWELL. 
LX. Proposal for an Apparatus for Flying by means of Moiion 
only, By A CoRRESPONDENT. 
To Dr. Tilloch. 
Sir, — Tur study of aérostation has hitherto been rather a 
subject of curiosity or amusement than of any real usefulness. 
The great expense attending the equipment of such an apparatus, 
as well as the extreme difficulty, next to impossibility, of guiding 
it through the atmosphere, have all along operated as powerful 
obstacles in turning it to any useful purpose. 
To remedy the latter inconvenience, an ingenious contrivance 
has been proposed by Mr. Evans, and published in your Maga- 
zine*.. There are different ways, | believe, in which a balloon 
might be conducted through the air, were it not for the weight 
of the materials employed. One of the most obvious would be 
to have a set of vanes or sails similar to those of a common wind- 
mill or smoke-jack attached to a horizontal axis, which being 
connected with the balloon, and turned swiftly round, would tend 
to push the whole in the direction of that axis. The huge bulk 
of the balloon, however, must always encounter much resistance 
from the air through which it attempts to force its way. 
If such av axis with vanes as has just been mentioned, but dé- 
tached from any balloon, were held in a vertical position and 
turned round with sufficient velocity in the proper direction, it 
would, from the reaction of the air, have a tendency to ascend ; 
and if revolving with such a velocity that the disposition to ascend 
* Vol. slvii. p. 429. 
might 
