58 Analyses of Books. [July, 



the hydrogen, we may infer that only the sulphur of two measures 

 united to the oxygen gas, and that the sulphur of 2} measures was 

 precipitated. 



" We may also infer from these data that the atoms of sulphurous 

 gas are surrounded with as large atmospheres of calorie as the par- 

 ticles of oxygen gas, or that they are as far asunder; and that the 

 number of the ultimate particles of sulphur in sulphureted hydrogen 

 are to those of the hydrogen as nine to five." 



This quotation is from p. 81 of the Comparative View, and from 

 p. 82 Of the work which we are at present considering. In this last 

 work Mr. Higgins subjoins to it the following paragraph : — 



" This was the first experiment of the kind made; and, had there 

 been no other evidence brought forward, ought to be sufficient for 

 the purpose, as it establishes three important facts which com- 

 prehend the whole of what has been unjustly called Dalton's theory. 

 1. The proportion of the constituents of an atom of sulphurous gas, 

 and the relative weight of those elementary principles. 2. The 

 weight of the atom, and comparative diameter of its calorific 

 atmosphere. And, lastly, The proportion of the ultimate particles 

 of hydrogen and of sulphur in sulphureted hydrogen gas." P. 84. 



Such are the claims and assumptions of Mr. Higgins, and such 

 the documents upon which these claims are founded. Now I deny 

 that there is the slightest allusion to the weight of a single elemen- 

 tally atom, either in these passages quoted, or in any part of the 

 Comparative View. Nor is there the slightest reason to induce us 

 to believe that the idea of ascertaining the weight of these atoms 

 has so much as entered into the conception of the writer. I admit, 

 without hesitation, that supposing Mr. Higgins to have conceived 

 the idea of determining the weight of the atoms of bodies, and to 

 have been aware of its importance in promoting the accuracy of 

 chemical analysis, the two preceding quotations would have enabled 

 him with facility to have calculated the weight of an atom of 

 hydrogen, oxygen, and sulphur. So would the analysis of car- 

 bonic acid by Lavoisier, which existed when Mr. Higgins wrote, 

 have enabled that philosopher, had he been aware of the importance 

 of the subject, to determine the weight of an atom of carbon; and 

 vhe analysis of ammonia by Berthollet and Austin have enabled 

 them to determine the weight of an atom of azote. 



1 lie process, supposing the idea once suggested, is one of the 

 simplest possible : but the great merit, I conceive, lay in suggesting 

 the idea. This was not done by Mr. Higgins, nor was any thing 

 even stated by him which could lead to the idea even in the loosest 

 manner. Now the opinion which 1 entertain is, that the only thing 

 new or important respecting the atomic theory, either in the writings 

 of Mr. Higgins or Mr. Dalton, is the method of determining the 

 weight!! of atoms. As this method does not exist in the work of 

 Mr. Higgins, but was fully txplained by Mr. Dalton, the merit 

 be!i ngs, I conceive, exclusively to him. 



It is not by the facility of a process, after it has once been sug- 



