Memorial on the upward forces of Fluids. 118 
steam-boats against snags, planters, sawyers shoals and rocks, 
Such materials, under protection of a national patent 
t, are well worthy of the attention oF philosophers and of 
mechanical philanthropists. For the full illustration of this 
subject, plates are necessary, which, by the liberality of the 
proprietor, ot be furnished, as far as necessary, in a suc- 
ceeding num 
The views dail plans of Mr. Genet are not all equally 
practicable, but no one of them requires more labour and 
comparative ingenuity than would have been ppenttn to be 
necessary, by the first navigator of an Indian canoe, had he 
been told that the same might, in the a of time, be con- 
verted into a line-of-battle ship of 124 guns 
here is a doubt, however, that may arise in the minds of 
many, concerning the correctness of the appellation or defi- 
nition of the upward forces of fluids, as adopted by Mr. Ge- 
net. Indeed, any kind of matter, or fluid, which is Ras Abe 
to have that tendency, owes it entirely, it if be! to grav- 
ity. Such is in fact the result of pressure downwar ardé: which 
causes a ‘ae alae ke ressure of the lighter bodies upwards. 
But on this r, Genet speak for himself, 
“In my m meditations on the homogenity of the forces usu- 
ally applied to mechanics, I have viewed with astonishment 
that the force of levity, or the upward force, should have 
been entirely overlooked and neglected; when Newton him- 
self had admitted the existence of a drawing force opposed 
to the force of gravity, which prevents the moon from falling 
upon the earth ; when Herschel had calculated that the force 
of levity, as exhibited rf re was such that it moved in 
every direction at the rate of 200,000 miles in a second ; 
Wlién the sinde ‘id the japeag OF the birth miltlaed a, by 
their ascension through the atmosphere, that hey were im- 
pelled by a force acting inversely to the force of gravity ; 
when that same force, which chemistry has proved to be due 
to ‘latent or ope was known to be the cause of the 
ascension of balloons ; when those zrostatic machines were 
seen to raise heavy w weights in a different tangent from the 
a of gravity ; when the report of the bold adventurers who 
sed themselves in the air, by the means of those zrostats, 
had d teste, that equally independent. of the general laws of 
atmospheric pres sure and aerometry, the elasticity of zerostats 
atid We nceelerated motion of their ascensio Oh Serer tee 
VOL. 1.—NO. 1. 15 
