196 : Miscellanies.. 
the gases in different receptacles and allowing them to meet during 
efflux. I have, however, operated in the large way upon the plan 
contrived and employed by Newman, Brooke, Clarke and others, 
having used at one operation nearly thirty gallons of the mixture of 
the gaseous elements of water. 
This I was enabled to do with safety by an improvement in Hem- 
ming’s safety tube. With this improved plan, I have allowed the gas 
to explode, as far into the tube of efflux as the point where the con- 
trivance in question was interposed, at least a hundred times without 
its extending beyond it. Still, however, the other mode in which 
the gases are separate until they meet in passing out of their respec- 
tive receptacles, is less pregnant with anxiety, if not with risk. As 
these elements are known to explode by the presence of several 
metals, other mysterious causes of explosion may be discovered. 
How much do I regret, that an ocean now rolls between myself 
and those respected and esteemed brethren in science whom this 
time last year [ had the pleasure to meet and greet at Bristol, and to 
whom I shall ever be grateful for their kind reception. How much 
would it gratify me, could I exhibit to them and their enlightened 
visitors, that splendid concentration of light and heat which I have 
latterly employed, by. which a metal infusible in the air furnace or 
forge, is made as fluid as mercury, so as to be blown off in globules. 
With the highest esteem, I am respectfully yours, 
(Signed,) Rosert Hare. 
Joun Datton, Esq., Chairman of the British Association 
for the Advancement of Science. ; 
7. Notice of the effect of Solar Heat in raising a Balloon, in 
a letter to the Editor, dated Hamilton, Upper Canada, April 17th, 
1837, from John Rae, Esq.—By the action of the sunbeams I 
caused a body of some pounds’ weight to ascend and float in the 
atmosphere, certainly at the height of a mile, probably of several. 
I will not detain you with an account of previous speculations and 
experiments but state the simple fact. Of paper blackened with 
China ink, of which I enclose specimens, I made a bag—the body 
of acylindrical form, one of the ends tapering toacone. The 
length of the axes of the cylinder and cone together eighteen feet, 
the diameter of the former ten feet and three quarters. At the apex 
of the conical part there was left an opening of about a foot in di- 
ameter secured by a circular piece of wire and having suspended 
