1909. | TUBERCULIN TES! IN MONKEYS. 83 
records taken at intervals of four hours during several days, in the 
existence of a marked daily rhythm or range in the case of every 
species of monkey examined, the high point being reached toward 
3 p.M., about which time a steady fall sets in amounting to three 
or four degrees by 3 A.M.; from then it rises again to the after- 
noon maximum. This daily range is shown in Chart A (text- 
fig. 1), and is in substantial agreement with the results reached 
by Simpson and Galbraith. It should be mentioned that few 
charts are as symmetrical as the one selected. 
Text-fig. 1. 
Chart A. 
a) 
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| a - 
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TIME 7AMINA.MI3 P.MI7 PR MJB MJ3 A.Mj7 AMI A.M)3 PM.|7 P.M.j1LP.M.}3 A.Mj7A.M.|11A.M13 PM. 
Cercopithecus pygerythrus $ adult. 
Temperature chart showing normal daily curve. 
In the beginning temperatures were taken for only twenty-four 
hours after injection, but it was found that reactions are some- 
times delayed until the second day, and an essential gain was made 
in extending the observation period to forty-eight hours. 
The course of procedure now followed in the tests is that when 
the daily temperature of the individual monkey has settled down 
to a somewhat regular course, an injection is made under the 
loose skin of the lumbar region of from # to 2 milligrams of Koch’s 
original tuberculin. This dose is only exceeded in case of ex- 
ceptionally large animals, such as anubis or chacma_ baboons, 
which have received as much as 3 mgs. Injection is made in the 
forenoon, in order that a rise of temperature concurrent with the 
upward tendency culminating about 3 P.M. may be noted. Tem- 
eratures are then taken at intervals of four hours for two full 
days. The hours we have selected as best indicating on the chart 
the daily course, are 7, 11, and 3. 
With healthy monkeys we have observed no change in the 
degree or course of the daily rhythm, following injection, nor ill 
results of any kind. 
6* 
