RELATIONS TO OTHER SCIENCES 683 



cesses alone gold to the value of $7,917,129 was recovered in the 

 United States in 1902, which is more than was ever won throughout 

 the whole world by all methods in any one year up to 1661, and 

 probably up to 1701. The data for other processes is not at hand for 

 1902, but the returns for 1900 show that gold to the value of $88,985,- 

 218 was recovered in the treatment of lead and copper ores in the 

 United States, of which $56,566,971 worth was recovered in refining. 

 It has but recently been publicly proclaimed in this city of St. Louis 

 that the "silver question" is settled, and it is settled, but it was 

 settled largely through the efforts of the technical chemist and metal- 

 lurgist. 



Technical chemistry renders important services to medicine in fur- 

 nishing it with an enormous variety of remedial agents, anesthetics, 

 and other supplies. It is an important factor in the public-health 

 service, supplying disinfectants and deodorizers, inspecting food- 

 supplies, supervising water-supplies, devising methods for the puri- 

 fication of sewage, the treatment of wastes, and the prevention of the 

 pollution of the atmosphere. We have but to mention the names of 

 Pasteur and Pettenkorfer, of Letheby and Wanklyn, and of Drown, 

 Chandler, and Mrs. Richards to emphasize the importance of the 

 chemical factor. 



Chemistry is an equally important factor in public safety. A 

 glance at von Schwartz's Fire and Explosion Risks will show how 

 varied and extensive but a single one of these fields of activity is. 

 Every one of you as you came here by boat or rail owed a large mea- 

 sure of your safe conveyance to the technical chemist. The regular 

 utilization of these valuable services in this interest is of quite recent 

 date. It was in 1875 that some of the officials of the Pennsylvania 

 Railroad Company, finding that the oil used in their signal-lamps and 

 headlightswas unreliable, and that all empirical methods of examin- 

 ation failed, determined to employ a chemist. Dr. Charles B. Dudley 

 was called, a laboratory was opened at Altoona, and in the face of the 

 skepticism of the " practical " man, the work began and was carried 

 to so successful an issue that a multitude of problems relating to 

 railroad administration have been referred to the chemist, his force 

 of skilled assistants has been steadily increased, and the position of 

 the chemist in the organization is second to none in importance. 

 Other railroad companies, recognizing the gain in economy and 

 efficiency, have also instituted chemical laboratories, until in thirty 

 years it has become common practice. While the Pennsylvania 

 Railroad Company was wrestling with the question of testing oil, the 

 U. S. Light-House Board was having trouble from the same cause, 

 the lamps in the light-houses and beacons along our coast, harbors, 

 and navigable waters having become quite unreliable from the char- 

 acter of the oil furnished, and it, too, sought the aid of the chemist, 



