4c84 
MR. GREEN THE EXPERIENCED AERONAUT. 
ance of the As?ociation at its next period of 
meeting, which were given according to the 
number of applications that had been made. 
These were from Newcastle-upon-Tyne, four ; 
Liverpool and Birmingham, two ; Manches- 
ter, one; Worcester, one; and Leeds, one. A 
consideraV'le discussion ensued, and it was at 
length decided that the next meetingshould be 
held at Liverpool, in the month of September, 
1837. The Karl of Burlington was appointed 
president ; Sir P. G. Egerton, Baronet, Dr. 
Dalton and the Rev. E. Stanley, vice-pre- 
sidents ; the Rev. James Yates and Dr. 
Turner, secretaries ; aud>-A. J. Murchison, 
Esq., general secretary, in the room of Mr. 
Daly, who had resigned. 
SCIENCE IN A BALLOON. 
Dr. Kent's Account of his Ascent loith Mr. 
W. Green from Vauxhall- Gardens, on Tues- 
day, August 30, 1836. 
Every arrangement having been completed 
for launching the balloons, the signal was 
given at five minutes past six o’clock, p. m , 
and they immediately rose, the wind blow- 
ing gently from S. W. The atmosphere be- 
ing remarkably clear, every object beneath 
us was seen with the greatest distinctness. 
We crossed the river a little to the eastward 
of London bridge, and the view at that period 
was most magnificent; St. Paul’s seen a 
little to westward ; the Monument nearer to 
us in the same direction ; the Tower almost 
immediately below us, the London Docks, 
the shipping, the extended view of the river, 
and the beautiful and highly- cultivated coun- 
try all around the metropolis, forming a 
coup d'oeil of the most sublime grandeur, 
which sets at defiance every attempt at de- 
scription. We crossed the river Lei a little 
to the northward of Stratford, at which time 
we had attained our greatest altitude, and en- 
tered a different current, which took us a little 
more to the eastward. M5e then passed over 
Epping Lower Forest and Wanstead Park, 
descending very gradually until we again 
reached terra firma at seven minutes pas'- 
seven, in a beautiful grass field, close to the 
Maypole, on the border of Hainault Forest, 
four miles N. E. of Ilford. Mr. C- Green 
having got into a different current, we soon 
parted company, but we had an exceedingly 
interesting view of his balloon until within a 
few minutes of his descent. This took place 
at Romford ; our chaises, however, met at 
Ilford, and we arrived together at the Gar- 
dens, Vauxhall, at eleven o’clock, p. m. It 
is but justice to Mr. W. Green to state, that 
his management of the balloon wa.s most 
skilful, and that the descent was accomplish- 
ed in the most easy and delightful man- 
ner. The greatest depression of the mercury 
in a barometer was 24.75 inches, which 
was its register at 6 h. 33 m., its height on 
leaving the ground having been ascertain- 
ed to be exactly 30 inches. The thermometer, 
which stood at 63 deg. Fahrenheit, or 17 deg. 
Centigrade, on leaving, sunk to 5l deg. 
Fahrenheit, or 10,4 Centigrade, at which 
point it stood at the abovementioned time. 
There was consequently a depression of 5.25 
inches in the height of the mercury of the 
barometer, and of 12 deg. Fahrenheit in the 
thermometer, indicating the greatest eleva- 
tion to have been about 5,863 feet, or 1 mile 
and 580 feet. A much greater altitude could 
have been attained, but it was thought de- 
sirable to make the descent before it became 
so dark as to render it probable we might be 
delayed in the emptying and packing the 
balloon. 
The management of the machine in the 
hands of an aeronaut so practised and intelli- 
gent as Mr, W . Green appears to be extreme- 
ly simple. After leaving the earth his atten- 
tion is first directed to the state of the dis- 
tension of the balloon, more particularly if 
the sun’s rays are falling on it. I'wo causes 
are then in operation which produce the effect 
of rarefaction and consequent expansion of 
the gas in the balloon ; one, the diminished 
atmospheric pressure, and the other, the ca- 
loric imparted by the rays of the sun. Should 
these causes act powerfully, it becomes ne- 
cessary to allow the escape of a small volume 
of gas from the safety-valve. Here ihe 
judgment of the aeronaut is called into ex- 
ercise, as he must allow a sufficient quantity 
of gas to escape, to prevent any undue disten- 
sion at the same time that it is necessary for 
him to bear in mind that he will have again 
to return into the same dense atmosphere he 
has left, when the balloon will, of course, 
contract into a smaller space than it previ- 
ously occupied. As long as the machine 
continues to rise, or is sailing along at the 
same altitude (which is ascertained by the 
barometer, or by the less scientific but readier 
method of throwing out small pieces of tissue 
paper and observing the direction they ap- 
pear to take), the above is the only point 
which requires his attention. When it is 
determined to commence the descent, either 
a small quantity of gas is again allowed to 
escape, or (if the balloon has already a ten- 
dency to descend) ballast is no longer thrown 
out, excepting as much as is sufficient to 
counteract in some measure the condensa- 
tion of the gas by the increasing density of 
the atmosphere. Having descended to within 
100 or 150 yards of the earth, an eligible 
spot for landing is selected, and the bal- 
loon is then allowed to descend again 
until the grappling-iron brings it to 
anchor, or the cord is secured by some of 
the persons attached to the spot. It is then 
drawn down gently by them, and as soon as 
the car rests on the ground, the valve is open- 
ed wide, the balloon is quickly emptied, and 
the whole being packed within, the car is re- 
conveyed to the spot from which a few hours 
before it arose. The safety-valve is situated 
at the top of the balloon, and is about eight- 
een inches in diameter. It is divided into 
two equal parts, each of which is kept closed 
by the action of powerful springs. Cords 
are fastened to either of these valves, which 
pass through the centre into the neck of the 
balloon, within reach of the individuals in 
the car. The valves are prevented from being 
opened too far by small pieces of twine fas- 
tened to them and to the ed^e of the aperture. 
When the ground is reached, and the machine 
secured, these are broken by a sudden jerk 
of the cords, the gas escapes rapidly, and 
the balloon collapses. 
Owing to the excellent management of 
Mr. W. Green, the balloon has not receiv- 
ed even a scratch by which it is damaged. 
Benjamin Archer Kent, m. h. 
20, Harley-street, Cavendish square. 
