yo AIDS TO BACTERIOLOGY 



Mortis Ointment. An ointment of tuberculin in lanolin. 

 The reaction is similar to that of von Pirquet. 



Calmette's Ophthalmo-TubercMlin Reaction. A solution 

 of old tuberculin freed from glycerin by precipitating 

 with alcohol is instilled into the conjunctival sac. In 

 a tuberculous subject a congestion of the conjunctiva 

 takes place. Calmette does not consider it of any value 

 in prognosis, and it is suggested by some as not safe 

 to use, 



The Opsonic Index. A healthy person's blood is cen- 

 trifuged in normal saline solution containing sodium 

 citrate. The leucocytes deposited are centrifuged with 

 normal saline. An emulsion of moist dead tubercle bacilli 

 (such as can be purchased) in 1-6 per cent, salt solution is 

 prepared. Equal volumes of washed leucocytes, bacterial 

 emulsion, and the patient's serum are drawn up into a 

 capillary pipette, and then blown out, mixed, and drawn 

 up into the pipette. The tip of the pipette is sealed in a 

 flame, but the blood must not be heated, as this destroys 

 the opsonic power, and an identical mixture is made, 

 using normal serum. The pipettes are incubated at blood- 

 h3at for fifteen minutes, and blood films are then prepared 

 from each and stained. The number of tubercle bacilli 

 in at least fifty polymorphonuclear cells is counted. The 

 index is found by dividing the number of organisms in 

 the specimen by the number in the control. Experience 

 and care are necessary to obtain comparable results. It is 

 general to examine the blood before and after some dis- 

 turbance of the focus, by walking and breathing exercises 

 in the case of pulmonary affections, or the application of 

 a Bier's bandage or massage if the focus be localised and 

 approachable. If fever be present, an inverse relation- 

 ship of opsonic curve to temperature suggests, tubercular 

 trouble. 



Johne's Bacillus. 



During life, Johne's -disease, a complaint peculiar to 

 the ox and sheep, is sometimes mistaken for tuberculosis. 

 The chief symptoms are diarrhoea and wasting. ' The walls 

 of the diseased bowel contain large numbers of an acid- 

 fast organism, ^morphologically indistinguishable from 

 the tubercle bacillus. Twort says that in the first genera- 

 tion the organism grows long, with branching and club 



