86 Capt. P. Yorke's Experiments and Observation? 



tube had lost *28 grain ; the water in the receiver weighed *06 

 grain only. 



16. In another experiment, an open test tube, containing a 

 solution of caustic potash, was placed in the bottle with the 

 lead and water. The white substance in question which form- 

 ed was dried in vacuo as before. A quantity, equal to 1*688 

 grain, was introduced into a green glass tube about S\ inches 

 long (a), into which was fitted, by grinding, the little tube {b\ 

 open at both ends, filled with chloride of calcium, and the 

 end of the tube (c), which was adapted to the end of tube 



c 



m^ 



UP 



(a) by a collar of caoutchouc, introduced under a jar full of 

 mercury. The tube (a) was then heated : a quantity of gas was 

 given off", equal *42 cubic inch, of which *16 cubic inch was 

 absorbed by caustic potash. The tube (b) had gained -05 

 grain; the tube (a) weighed when cold, had lost '158 grain. 

 Yellow oxide remained. 



17. In another experiment with the same apparatus 1*314? 

 grain gave off a portion of gas which was absorbed by potash, 

 but from an accident the quantity was not estimated. The 

 chloride of calcium gained *036 grain, and the tube (a) lost 

 •154 grain. 



18. If the whole loss sustained minus the quantity of water 

 collected be reckoned as carbonic acid, we have as the result 

 of the last two experiments : 



Ex. 2. Ex. 3. 



Oxide of lead I' 53 1*16 



Water 0*050 0*036 



Carbonic acid 0*108 0*118 



1*688 



1*314 



Ex. 1. 



89*5 



Or, in 100 parts, Ex. 2. 



Oxide of lead 90*63 



Carbonic acid 6*341 



Water 2*96 J 



10. These experiments are not sufficiently accordant, nor 

 made on large quantities enough to determine whether the 



9*3 



Ex.3. 



88*28 

 8 

 2 



:?®}ll.72{lO-5 



