m^ COMBINATfONS OF PXIMURIATIC GAS AKD OXIGEN. 



manner by their difficult fusibility from the potash and soda 

 prepared by alcohol. 

 Wattr in the Mr. D*Arcet, and more distinctly Mr. BerthoUet, have 

 alKalis. concluded, that the loss ot weight of common fused potasli 



and soda, during their combination with acids, depends 

 upon the expulsion of water, which Mr. BerthoUet has rated 

 at 13*9 per cent for potash, and Mr. D'Arcet, at 27 or 28 

 for potash, and 28 or 29 for soda *. 



1 have stated in the last Bakerian lecture, that my own 

 results led rae to conclude, that fused potash containe4 

 about l6 or 17 parts in the 100 of water, taking the potash 

 formed by adding oxigen to potassium as a standard. 



The experiment, from which 1 drew my conclusions, was 

 made on the action of silex and potash fused together, and 

 I regarded the loss of weight as the indicj^tion of the quan- 

 tity of moisture. 

 Water not yet 1 am acquainted with no experiment on record, in which 



collected from ^^atep |,as been actually collected from the igrnited fixed 



the Ignited al- . , " 



kalis. alkalis, and this appeared necessary for the complete elucif 



dation of the subject. 

 Experiment to 1 heated together, in a green glass retort, 40 grains of 

 •flfect this with potag},^ (that had been ignited for several minutes), and 100 

 ^'' grains of boracic acid, which h.id been heated to whiteness 



for nearly an hour. The retort was carefully weighed, and 

 connected with a small receiver, which was likewise weighed; 

 the bulb of the retort was then gradually heated till it be- 

 came of a cherry red ; there was a violent effervescence in 

 the retort, a fluid condensed in the neck, and passed into 

 the receiver. Whep the process was completed, the whole 

 Wat« 0»17? of the retort was strongly heated; it was found to have lost 

 6f grains, and the receiver had gained 5'S grains. The 

 fluid that it contained was water, holding in solution a mir 

 nute quantity of boracic acid, and when evaporated, it did 

 not leave an appreciable quantity of residuum* 

 Water from A similar experiment made upon soda, heated to redness, 

 but in which the water collected was not weighed, indicated 

 22*9 of water in 100 parts of soda. 



* Annales de Chimie, torn. 08, page l90; or Journal, vol. XXVII, 

 page 31. - 



or 0-19? 



s«da 0-23. 



