1SH.] Higgins on the Atomic Theory, &c. 53 



gested, that we are to estimate its value; but by the new light 

 which it throws upon the subject of our investigations. All the 

 mathematical discoveries of Sir Isaac Newton were the direct con- 

 sequence c'i his extracting the square root of -i-. Nothing at present 

 appears easier or simpler; yet the fluctionary calculus, and the 

 immense progress which the science has since made, were the imme- 

 diate result of that operation. It had baffled the sagacity of Dr. 

 Wallis, who was no ordinary man ; but, on the contrary, nest to 

 Newton, the most original mathematical genius of his age. In 

 like manner the method of determining the weight of atoms, a 

 process in itself extremely simple, baffled the sagacity of Mr. 

 liitrgins, but was accomplished by Mr. Dalton. 



I must be permitted to say that, as far as my scientific knowledge 

 goes, there never was a more unwarrantable claim made since the 

 days of Aristotle than this claim of Mr. Higgins ; and I cannot 

 see without regret a man of his respectability and talents engaged in 

 a dispute, from which he has put it out of his own power ever to 

 retract. He must persevere in his allegations to the end. But the 

 Comparative View stands in his way as an evidence against him, 

 which no assertions on his part, or those of his friends, no display 

 of eloquence, however pathetic, can ever overcome. 



There is one other point on which Mr. Higgins lays considerable 

 stress that I had almost forgotten to notice. He employs, in his 

 diagrams and his reasoning, figures to denote the strength of affinity 

 of different bodies for each other. This he calls mathematical 

 demonstration, considers it as his own invention, and affirms that 

 chemistry will never make effectual progress till it becomes general. 

 I beg leave to observe, that the same thing was done long before 

 him by Dr. Black and by Bergman, as may be seen in his diagrams 

 of double decompositions in his well known essay on elective attrac- 

 tions. Morveau published a table expressing by numbers the affini- 

 ties of different bodies, in the first volume of the chemical part of 

 the Encyclopedic Methodique, several years before the Comparative 

 View appeared. As to the originality of the idea, therefore, there 

 can be no doubt that it does not belong to Mr. Higgins. As to the 

 value of the practice, I own myself of a different opinion from our 

 author. The numbers are merely arbitrary ; hence they give a 

 greater appearance of precision to our chemical reasonings than they 

 are warranted to assume ; and as it is next to impossible to pitch 

 upon numbers that represent the real strength of affinity exerted by 

 the bodies in question, these numbers must frequently mislead us, 

 and induce us to draw results contrary to truth. 1 soon found this 

 to lie the case with Morveau'fl table. 1 was at the trouble to con- 

 struct another, which I fancied was more accurate, but soon met 

 with cases in which it likewise was erroneous. Hence I discarded 

 numbers altogether. Jt is needless to observe that empirical 

 numbers, taken at random, never can lead to any thing entitled to 

 the same of a legitimate mathematical demonstration. 



1 will just hint at another thing upon which Mr. Higgins has 



