584 MICUOBIOLOGY OF SPECIAL' INDUSTRIES 



Other Tuberculins. — ^Koch introduced tuberculin "T. R." (tuber- 

 culin residuum) in 1897 and tuberculin, "B. E." (bacillary emulsion) in 

 1901 . The former is.prepared by repeatedly centrifugalizing a suspen- 

 sion of the dried and ground tubercle organisms in water. The super- 

 natant fluid "T. 0."faifter the, first centrifugalization is discarded and 

 the final product consists of the constituents of the bacteria which are 

 insoluble in water. ;One cubic centimeter of the tuberculin "T. R." 

 should contain the equivalent of 2 mg. of the dry tubercle soUds. 

 Tuberculin B. E. is composed of a suspension of crushed or thoroughly 

 ground tubercle organisnis in 50 per cent glycerin solution. Each 

 cubic centimeter should contain the equivalent of- 5 mg. of tubercle 

 solids. .Tuberqulin T. R. and tubercuUn B. E. are used as therapeutic 

 agents, the latter probably being regarded with more favor by clini- 

 cians. The material is administered by subcutaneous injection, the 

 time intervening between successive treatments varying from three to 

 ten days.' The initial dose recommended by most investigators, 

 is o.oooi mg. or less. ■ " 



Mallein. — MaUein is prepared from cultures of BacL mallei by 

 practically the same, methods as those employed in manufacturing 

 tuberculin from Bact. tuberculosis. The product is used for the diag- 

 nosis of glanders. A few hours after maUein is injected, subcutaneously, 

 into glandered horse&a severe local reaction and a rise of temperature 

 usually follow. The thermal reaction is very, similar to that produced 

 in tuberculous animate by the injection of tuberculin. The local swell- 

 ing caused by maUein treatment is, considered by some to be quite as 

 diagnostic as the temperature reaction. 



The ophthalmic mallein test, a comparatively recent method, which 

 was first used by Choiomansky, appears to be attaining considerable 

 recognition as a valuable aid in diagnosis. The test consists in the 

 application of concentrated mallein to the inner canthus of the eye. 

 A drop of the concentrated mallein in liquid form or a small bit of the 

 same in desiccated condition may be used. In a positive case, 

 hyperemia and swelling of the conjunctiva and a purulent exudate at 

 the inner canthus of the eye will appear from four to six hours after the 

 instillation of the mallein. 



Goodall* advocates the use of the intrapalpebral mallein test which 



* Goodall, Jour. Comp. Path, and Therap., igis. Vol. 28, p. 281. 



