310 A Sketch of the Laws of Chemical Combination. 



wliich it was observed, though so long unperceived by them, was strikingly 

 exliibited in every object they beheld. In confirmation of this, a venerable 

 and grey-headed man, (whom Mr. Conybeare appropriately terms the 

 Polynesian Paley,) who had formerly been a sorcerer or priest of the evil 

 spirit, stretched forth his hand, and, looking at the limbs of his body, said; 

 'Here the wisdom of God is displayed : — I have hinges from my toes to 

 my fingers' ends ; this finger has its hinges, and bends at my desire ; this 

 arm, on its hinges, is extended at my will ; by means of these hinges, my 

 legs bear me where I wish ; and my mouth, by its hinge, masticates my 

 food. Does not all this display the wisdom of God ?' " 



A SKETCH OF THE PRESENT STATE OF OUR KNOWLEDGE 



or THE 



LAWS OF CHEMICAL COMBINATION, 

 WITH SOME OF THEIR MORE IMPORTANT APPLICATIONS. 



In watching the progress of those branches of science which are most 

 rapidly advancing at the present time, we may generally observe that 

 whilst apparently becoming more complicated and difficult of attainment 

 through the rapid accumulation of individual facts, they are really in- 

 creasing in simplicity, owing to the discovery of general laws, which are 

 based upon some of these facts, and lead to the knowledge of many others. 

 " Every new discovery in science," says Sir J. Herschell, (Discourse on 

 the Study of Natural Philosophy, p. 358) "brings into view whole classes 

 of facts which would never otherwise have fallen under notice at all, and 

 establishes relations which afi'ord to the philosophic mind a constantly ex- 

 tending field of speculation, in ranging over which it is next to impossible 

 that he should not encounter new and unexpected principles." Perhaps 

 Chemistry affords more abundant proofs of the truth of these observations 

 than any other branch of Science j for whilst our knowledge of the com- 

 binations formed by substances that are usually considered elementary is 

 every day being extended by the labours of the practical chemist,* the 

 discovery of many of the laws which regulate these combinations has not 

 only led to a very simple classification of them — easily understood and 

 remembered — but is constantly pointing to the investigation of new com- 

 pounds which afford remarkable verifications of their truth. To give a 

 sketch of the present state of our knowledge of these laws, and of some of 

 their more interesting applications, is the object of the present paper. 



The elementary or simple bodies, whose existence is now generally re- 

 cognised, amount to fifty-four: but it is not impossible that their number 



* Berzelius has lately published a list of upwards of 4500 of the most important 

 of these combinations, confining himself principally to the inorganic. — Theorie des 

 Proportions CMmiques, Second Edition, 1835. 



