Thomson's Sifstem of Chemist ri/. 157 



the heat, either alone, or in the state of an oxide, soluble in 

 water. His preceding scheme * of analyzing this powder by- 

 nitrate of silver, was still worse : it was a method which would 

 lead the bleacher to believe, that his powder was strongest, 

 when in reality it was weakest, or altogether inert. For when 

 the chloride of lime passes into the common muriate, as by 

 keeping, Sfc, the precipitate by nitrate of silver attains a 

 maximum. 



When we read his next article, on muriatic acid, we are 

 tempted to exclaim with the old statesman, Nescis, mi fili, 

 quara parva scientiS, libri quidam conficiuntur. " A cubic 

 inch of water," says he, " at the temperature of 60°, barometer 

 29.4, absorbs 515 cubic inches of muriatic acid gas, which is 

 equivalent to 308 grains nearly. Hence water, thus impreg- 

 nated, contains 0.548, or more than one half its weight of 

 muriatic acid, in the same state of purity as when gaseous. I 

 caused a current of gas to pass through water, till it refused to 

 absorb any more. The specific gravity of the acid thus ob- 

 tained was, 1.203. If we suppose that the water, in this ex- 

 periment, absorbed as much gas as in the last, it will follow 

 from it, that 6 parts of water, by being saturated with this gas, 

 expanded so as to occupy very nearly the bulk of 11 parts, but 

 in all my trials, the expansion was only to 9 parts. This 

 would indicate a specific gravity of 1.477 ; yet upon actually 

 trying water thus saturated, its specific gravity was only 1.203. 

 Is this difference owing to the gas that escapes during the taking 

 of the specific gravity f ?" This nonsense is quite deliberate. It 

 is copied verbatim from his fifth edition. Yet the whole is an 

 affair of simple proportion, level to the capacity of the youngest 

 school-boy. 100 cubic inches of muriatic gas weigh, according 

 to him, 39.162 grains ; hence 



(1.) 100 : 39.162 : : 515 : 201.6843, and not " 308 grains 

 nearly," as be states. 



(2.) (25.252 + 201.68) : 201.68 : : 100 : 0.444, and not 

 " 0.548, or more than half its weight." 



(3.) 252.52 : (252.52 -|- 201.68) : : 1 : 1.798= the increased 

 weight, which a volume of water acquires by combining with 

 515 volumes of muriatic acid gas. And the volume being in- 

 versely as the specific gravity, if we divide that weight by the 

 given specific gravity, we shall have the volume of the liquid. 

 Hence 



(4.) L!l«== 1.4946 

 1.203 



• Annals of Philosophy, March, 1819, p. 182. 

 t System, il. 245. 



