ON THE NATURiT OF OXIMURIATIC GAS. 315 



partly from overlooking, that a light powdery substance 

 like muriate of ammonia, independent of its chemical at^. 

 traction, absorbs water hygroraetrically. Mr. Davy has Muriate of 

 informed me, that this is the case, and that muriate of ^™ J^J^^^J"* 

 ammonia so made absorbs so much, that it even deli- quescent. 

 quesces. 



Mr. Murray's confidence in his result, which is opposed 

 by several facts relative to muriate of ammonia, is to me 

 more surprising than the result itself. 



It is well known, that muriatic acid gas condenses its own No water to 



volume of aramoniaca! gas to form muriate of ammonia, f/'^"''^ ^""*' 



. ' tic gas, if ad- 



which, from trials I have made of its properties, does notdedip. excess. 



appear to differ in any respect from common sal ammoniac. 

 This being the case, if water is liberated on the union of the 

 two gasses, it should, were Mr. Murray's experiment cof" 

 rect, be indicated by an absorption of muriatic acid gas, 

 provided an excess was used. 1 have madt^the experiment, 

 but have not observed the slightestdiminution ofthe gas ad«» 

 ded ir» excess. 



These facts, though mentioned last, first convinced me of Water not 

 the inaccuracy of Mr, Murray's experiment, for they were the unfon'of 

 first ascertained. They confirm the other decisive eviden-r ammoniacal 

 ces already brought forward ; and, if farther proof was re- ^"j^ ^s"^*'*^ 

 quired* I could advance additional circumstances to show, 

 that water is not produced, when the union qf muriatic acid 

 gas and ammoniacal gas takes place. As this appears to me 

 to be demonstrated, the necessary consequence is abiding by Nece-sary con- 

 the experimentum crucis, and renouncing that hypothesis, sequence of 

 to which It stands opposed : indeed Mr. Murray allows, experiment. 

 that, should the event turn out as it has, such a step must 

 be taken : he allows, if water is not produced, " that it 

 may be concluded, that the water obtained in other combi- 

 pations of muriatic acid gas has not preexisted in it, but is 

 ready formed;" that Mr. Davy's theory, in short, is correct, 

 9nd the old doctrine erroireous. Should he not make this 

 acknowledgment, I th»nk he will no longer assert, guided 

 by his own experiment, that Mr. Davy's theory is un- 

 founded, and that it can be maintained only by the most 

 gratuitous assumption; or thattp admit it, it is necessary to 



suppos^t 



