198 TRAXSACTIONS 01- THE [.MAKCll 15, 



The alchemists labored to transmute base metals into noble 

 ones, and were destined never to realize their ambitious designs; 

 modern organic chemists, operating on substances compared 

 with which even the base metals are precious, 'produce articles 

 more beneficial to mankind than gold itself, and, at the same time, 

 gain, indirectly, no small store of the coveted metal. 



(21.) The application of chemistr}' to i)hysiology encounters 

 the most complex and difficult ])roblems in the science, and at 

 the same time aims to accomplish the most beneficent results. 

 ^' The physiologist complains that ])robably ninety-five i)er cent 

 of the solid matters of living structures are pure unknowns, and 

 that the fundamental chemical changes which now occur during 

 life are entirely shrouded in mystery. It is in order that this 

 may no longer be the case that the study of carbon compounds is 

 being so vigorously prosecuted."'* It may seem strange to the 

 non-})rofessional in this audience that, in spite of persistent and 

 skilful attempts to solve the problem, chemists are obliged to 

 admit ignorance of the exact composition of so common a sub- 

 stance as the white of egg, yet until they acquire an accurate 

 knowledge of the constitution of albuminous substances, the 

 processes of animal economy cannot be explained. While the 

 physiologist, in some degree, waits on the organic chemist for 

 further developments, the latter discovers and prepares novel 

 bodies much faster than the physiologist ascertains their influ- 

 -ence on the animal economy. To the joint labors of chemists 

 and physiologists are due the blessings of anassthetics, hypnotics, 

 and other conquerors of suffering and disease. The ana3sthetic 

 properties of cocaine, and the circumstances of their discovery arc 

 matters of popular knowledge. AVithin a twelvemonth, e'thyl- 

 urethane has been added to the list of hypnotics. 



In recent years, sanitary chemistry has acquired great impor- 

 tance, and now occupies a distinctly defined field, including all 

 that pertains to the hygienic value of foods and beverages, their 

 adulterations, and their fraudulent substitutes ; questions of gas 

 and water supply ; of the uses and abuses of disinfectants ; of 

 household ventilation, and of the diverse matters grouped under 

 the term chemical engineering. Of tiiis very ]>ractical branch of 

 chemical science, as well as of the valuable additions to materia 

 medica, of the improved methods introduced into analytical 

 chemistry, and of the ever increasing contributions to the chem- 

 istry of agriculture, no mention can be attem})ted. 



(22.) The tendency of modern researches in chemistry is to 

 magnify the atomic theory; the rapid accumulation of facts, the 

 ever increasing ingenious hypotheses, tlie most searching exami- 

 nations of co-ordinate laws, all tend to strengthen the Daltonian 

 adaptation of tiie philosophic Greeks. Here and there a voice is 



