^ THE MANUPACTURE OF ANTISERUMS 583 



Calmette,* von Pirquetf and Morof may be used in human practice, 

 Calmette's ophthalmo test consists in the instillation in the eye of 

 Koch's purified or refined tuberculin. Purified tuberculin is prepared 

 by treating the original tuberculin with absolute alcohol, washing and 1 

 drying the precipitate. One drop of a ,1 per cent solution of purified 

 tuberculin is placed in the eye. A positive reaction is manifested by a 

 congestion of the palpebral and ocular conjunctiva a few hours after the. 

 application of the tuberculin. The method of von Pirquet* depends 

 upon the cutaneous application of the tuberculin. One drop of tuber- 

 culin (old) is placed on the arm, after cleansing the skin, and the small 

 area under the drop is scarified. Two or more small areas may be 

 treated in this way, as well as a control area treated with sterile salt 

 solution or a solution of glycerin and dilute carbolic acid in substitu- 

 tion for the tuberculin. The appearance of a reddish zone in from 

 twelve to twenty-four hours indicates a positive reaction. This area 

 of inflamn^ation gradually increases somewhat in elevation and diameter , 

 and finally subsides in a few days. Moro's modification of von Pir- 

 quet's method consists in the use of tuberculin ointment prepared by the 

 combination of tuberculin (old) and anhydrous lanolin in equal parts. 

 The ointment is vigorously rubbed on a small portion of the skin of the 

 abdomen. A positive reaction is evidenced by the appearance of a 

 distinct granular or papular eruption at the point of application after 

 about twenty-four hours. 



For the diagnosis of tuberculosis in cattle, the intradermal test is 

 generally regarded as next in importance to the older subcutaneous test. 

 In conducting this test o.i to 0.3 cc. of a 50 per cent solution of tuber- 

 culin is injected into the cuticle layer of the skin at the base of the 

 tail. A positive reaction is present when, twenty-four to seventy-two 

 hours after the injection of tuberculin, the localized area of skin shows 

 a circumscribed cedematous swelling. 



Tuberculin (old) is usually distributed in small vials, sealed and 

 labeled. The labels should indicate the amount and dosage and the 

 date of preparation. Under the influence of light and heat the fluid 

 product may slowly deteriorate; therefore, when possible, it should be 

 kept in the refrigerator until needed. 



* Calmette, Presse Medicate, 1907, 15. 

 f von Pirquet, Berl. klin. Woch., 1907, 44- 

 j Moro, Mfinch. med. Wch., 1908. 



