Page:The Liquefaction of Gases.djvu/79

Rh eye of the public: if upon that repetition they appear to me to be attended with results of sufficient importance to occupy a place in your Journal, I will take the liberty of communicating them to you, and am. Sir, Your most obedient servant, THO. NORTHMORE.

P. S. I think it necessary to add, that during the course of the above-mentioned experiments, there was a great variation of temperature in the atmosphere, from the heat of 70 degrees of Fahrenheit to the cold of 33.

SIR,

NOW take the liberty of presenting you with a continuation of my experiments upon the condensation of the gases, but first beg leave to make one observation, viz. that the quantity of gas said to be injected in each experiment, cannot (particularly in the preceding article) always be depended upon; for its tendency to escape is so constant and powerful, as frequently to elude every effort of mine to prevent it, and if it can find no other exit, it will sometimes escape by the side of the piston of the forcing pump. In the preceding experiments I have endeavoured as much as possible to obviate this evil, but not always with the success that I could wish.

Repeating the eighth experiment mentioned in my former letter, (see Vol. XII. p. 372-3) viz. the