322 On Aérial Navigation. 
forces, and not having a proper first mover, I was obliged to 
try the experiments as to steadiness and steerage by merely al- 
lowing the vessel to sail from the top of a hill; and it was to 
this circumstance that I alluded in my observations upon Mr. 
Evans’s paper, the descending half of the movement that gentle- 
man proposed being perfectly similar to, and therefore corrobo- 
rated by my experiments. . 
Ihave related this matter more minutely, because Mr. Edge- 
worth’s statement rather gave me a claim to the principle of 
steering balloons by means of the inclined plane, which | do not 
possess. Indeed I ‘hold it perfectly in my recollection, (although 
I cannot state either the name of the party or the publication 
in which | read the account,) that an ingenious young man se- 
veral years ago had tried some successful experiments on the 
steerage of balloons by the inclined plane, but had died before 
he completed his invention. 
Should this subject gain importance by experimental success, 
this, and no doubt many other claims of various kinds, will be 
attempted to be placed over the heads of those gentlemen, who 
now will, I hope, have the more substantial credit of realizing 
and perfecting the invention for the uses of mankind. For my 
own part, I shall sue for no share in the scramble respecting 
Montgolfier balloons, but that of braving the risible muscles 
of my y friends in substituting acres for yards of ctoth in their 
structure, unless indeed it be for the addition of. a chimney, a 
most common, natural, and in this case particularly useful ap- 
pendage to a fire. I shall however be extremely gratified in 
being able to claim the credit of standing on the same list with 
Mr. Edgeworth as a subscriber towards at this noble ‘ 
art ;—with this view I request Mr. Tilloch to be kind enough 
to permit a list of subscriptions to remain at his house till a few 
names be collected and a committee appointed* ;—no one to be 
called upon for bis subscription money till such a sum be sub- 
scribed for as will be sufficient to try the first experiment pro- 
posed by the committee. 
In my last paper it was stated that I had made some calcu- 
lations relative to the quantity of fuel that would be consumed 
in propelling the Montgolfier balloon there described, at a ve- 
locity of twenty miles per hour, by the steam- -engine. According 
to the returns made of the Cornwall engines, Mr. Woolf’s 
engine raises about fifty millions of pounds, one foot high, with 
a bushel or eighty-four pounds of coal. Hence | estimate that 
twenty pounds of coal per mile would be consumed in this ope- 
* T can have no objection to keep a list of the names of such gentlemen as 
may wish to contribute to an experiment of the kiad recommended.—A. T. 
ration, 
PE 
