126 The Evolution of Chemistry. 



tie later date the first of these was dropped and thencefor- 

 ward, for some fifteen hundred years, the doctrine of the 

 four elements dominated philosophy. When we critically 

 examine Aristotelianism on its chemical side, we discover 

 that abstract principles or supposed qualities, and not things, 

 were by its advocates deemed the actual elements. They 

 took all extended bodies to be continuous in structure, and 

 thought them capable of becoming anything or everything. 

 We see this in the language of the founder of the system 

 when he tells us that " fire is hot and dry, air is hot and 

 moist, water is cold and moist, and earth is cold and dry." 

 When ordinary water is boiled away to dryness an earthy 

 residue is found. This was explained as the heat of fire 

 vanquishing the moist of water and leaving the dry of fire 

 combined with the cold of water. Dry and cold being to 

 them earth, of course a residue must, by their logic, be ex- 

 pected. The establishment of alchemy among such think- 

 ers was inevitable. If the opposing qualities of substances 

 demolish each other and the residual ones form new sub- 

 stances, transmutation is a necessity. 



The word Chemeia (Chemistry) first occurs in a Greek 

 lexicon of the eleventh century. The definition given is 

 " the preparation of gold and silver." Such indeed we 

 know to have been the aim of early chemists. Later on 

 attention was directed to the preparation of medicines. 

 The prefix " al " before chemist simply means " the " i. e., 

 the chemist. It is the Arabic definite article. Alchemy 

 was a natural outgrowth of the four-element theory, but 

 the necessity of experiments engendered by it was fatal to 

 such a metaphysical structure. Where abstractions take the 

 place of facts the laboratory should be excluded as danger- 

 ous. For their unique way of reasoning about how gold 

 could be made, the old elements failed to give expected re- 

 sults. Not suspecting that their reasoning might be at 

 fault, they proceeded to hunt for new elements better able 

 to match their logic. Sulphur was found by combustion 

 to produce fire and a gas which they took to be air. Be- 

 sides, it had a yellow color, a quality of gold which the old 

 elements lacked. Mercury had the fluidity of water and 

 likewise possessed the quality " metal," a condition very 

 much needed in gold-making. Salt contained all the quali- 

 ties not found in sulphur and mercury, but necessary to 

 form a world. Thenceforth sulphur, mercury, and salt took 

 the places of air, fire, earth, and water. The introduction 



