Development of the Chemical Industry 11 



yield by attempted oxidation of naphthalene by means of 

 sulphuric acid was too small. It so hai)pened that in one 

 experiment the mercury thermometer broke, where- 

 upon it was found that the reaction of the material 

 became very animated, and the yield of phthalic acid by 

 heating naphthalene with sulphuric acid in presence of 

 mercury was almost theoretical. The accidental break- 

 ing of a mercury thermometer led to a very important 

 discovery which became the basis of a cheap way of 

 making indigo. These are only a few instances in which 

 new chemical manufacturing plants have been established 

 on a large scale on the basis of laboratory research. 

 Many other industries followed, among which the manu- 

 facture of medicinal chemicals has become most impor- 

 tant. 



For the preservation and possible development of many 

 industries which have sprung up during the war, when 

 importations of chemicals were impossible, a liberal tar- 

 iff and a wise patent law are most desirable and almost 

 imperative. Particularly the dyestuff industry will have 

 a hard fight for its existence. At a recent meeting of 

 manufacturers in New York, a petition was formulated 

 and sent to Congress asking for an embargo on the 

 importation of dyestuffs, since manufacturers realized 

 that nothing short of an embargo could save the indus- 

 try, until a complete and liberal revision of our tariff 

 law has been enacted. Of equal importance would seem 

 to be a wise revision of our patent law. Many chemicals, 

 particularly of the medicinal variety, are now manu- 

 factured abroad at a much lower price than in the United 

 States. 



The third branch of chemical research and manufac- 

 ture, agricultural and biological chemistry, is repre- 

 sented by Justus V. Liebig and his school. Being a part 

 of organic chemistry, it differs from it in that it does not 

 attempt to make its products in the chemical laboratory, 

 but is endeavoring to ascertain the conditions and 

 requirements under which plants and animals will grow, 



