Industrial Research 



263 



fuge, electrophoresis, and (lifl'iision apparatus, arc em- 

 ployed in determining tlie purity and nature of tuber- 

 lin. Further biological research is still needed on this 

 product. 



Chemical Products 



Chemotherapy. — The treatment of disease with chem- 

 ical substances that selectively destroy the harmful 

 organism without doing serious injurj^ to the animal is 

 the object of numerous researches. The recent dis- 

 covery of sulfanilamide and its remarkable therapeutic 

 properties, and the still more recent findings of Dubos 

 regarding the products of micro-organisms to be used 

 in the treatment of disease indicate the significance and 

 possibilities of research iir this field. 



Fungicides, insecticides, germicides, detergents. — The 

 crops of the farmer are constantly being threatened by 

 parasitic plants, smuts, mildews, rusts, and wilts, and 

 by such insects as the grasshopper, the potato beetle, 

 the codling moth; his animals are threatened by various 

 micro-organisms. The building industry must consider 

 the wood-destroying fungi, blue stain fungi, and insects 

 such as termites. The textile industry also must give 

 consideration to the same agencies, for all textiles are 

 exposed to the destructive action of fungi and bacteria, 

 and the textiles made from animal fibers, such as silk 

 and wool, are attacked by clothes moths and other 

 destructive insects. The organic matter produced on 

 the farm is exposed to attacks of varied rodents, as is 

 organic matter in transportation and processing. 



The development of products used to protect material 

 against the action of these various destructive forms 

 is an important industry in which the biologist must 

 find a place. The larger producers of these products 

 find it necessary to maintain experimental colonics of 

 the species to the influence of which their products 

 are exposed. In dealing with green plants, there has 

 been developed a method for controlling the growth of 

 weeds by the use of sodium chlorate. 



The detergent industry is a very old one. However, 

 it is one in which great progress has been made during 

 recent years. The value of soaps as agents to remove 

 and to inhibit the growth of various mici-o-organisms 

 has not been recognized. The development of any 

 compound which shall have marked action as a wetting 

 agent has found great use not only in the textile indus- 

 try but also in the application of fungicides which, 

 without adequate wetting power, cannot be uniformly 

 distributed over the surface of plants on which they 

 are used. The biological role of detergents has not 

 been widely recognized. In the cleansing of all types 

 of food utensils, especially those in which various types 

 of bacteria exist, reliance has been placed on the destruc- 

 tion of the micro-organism by some harmful agent such 

 as heat. In many connections this agency has distinct 



limitations. It can be partially overcome through the 

 action of effective detergents which will aid in removing 

 protective films of organic matter as well as micro- 

 organisms. There has been rapid development in all 

 of these fields in recent years, but much still remains to 

 be accomplished. The use of dilute solutions of sodium 

 hydrate, trisodium phos[)hate, and metasilicatc in the 

 dairy has aided in the i)roduction of milk with low 

 bacterial content. 



Relation of parasites to industry. — The harmful effect 

 of parasites on workers in certain countries offers a 

 serious handicap to industry. Investigations have 

 shown that the presence of a hundred or more hook- 

 worms exerts a measurable eft'ect on the mental and 

 physical development of an individual. The occurrence 

 of hookworm and malaria in certain sections may 

 become so prevalent that it is advantageous to locate 

 the industrial plants outside these endemic areas. The 

 coffee and tropical-fruit industries must operate in 

 endemic areas of parasites, hence the clear recognition 



Figure 83. — Determination of Thermal Death Time of Micro- 

 organisms, H. J. Heinz Laboratories, Pittsburgh, Penn- 

 sylvania 



