38s ©. M. Warren on Organic Elementary Analysis. 
position products, containing the hydrogen, had been burut at 
the expense of oxyd of copper. 
By a very simple device I entirely obviate the danger of ex- 
os 
control the distillation of volatile substances and prevent too 
rapid combustion; it being essential in this, as in other pro- 
the combustion should proceed slowly, and with & 
good degree of regularity; otherwise it would be difficult to 
regulate the supply of oxygen to meet the demand of the burn- 
ing substance. By having the column of asbestus of consider- 
able length, the anterior end of which only is ignited, the sub- 
stance, if volatile, becomes diffused through a large “ee and 
the distillation thereby easily controlled, as only a small portion 
of the substance need then be heated at a time. Doubtless @ 
-+ Thave used only asbestus in my experiments thus far, and in every instance 
