DOSAGE OF THE MAMMALIAN HEART BY CHLOROFORM 85 
TADPOLES 
CHC1 3 per thousand 'modified Ringer's solution,' and CHC1 3 1-5 per thousand defibrinated blood, 
unlaked (pig). (1 in 1,000 by volume). 
Chloroform in ' Ringer ' 
Chloroform in Blood 
Reflexes gone 
50 sees. 
Recovery 
8 mins. 
Reflexes gone 
p mins. 50 sees. 
Recovery 
5 mins. 
CHCI3 -75 per thousand 'modified Ringer's fluid,' and CHC1 3 75 per thousand defibrinated blood, 
unlaked (pig), (i in 2,000 by volume). 
Chloroform in 'Ringer' 
Chloroform in Blood 
Tadpole A 
„ B 
Reflexes gone 
2 mins. 30 sees. 
2 mins. 1 5 sees. 
Recovery 
2 mins. 25 sees, 
(begins) 
4 — 5 mins 
Tadpole B 
„ A 
Reflexes gone 
p mins. 
(not fully narco- 
tized) 
7 mins. 
hardly narcotized 
Recovery 
revives at once 
revives at once 
CHCI3 75 per mille 'modified Ringer's fluid,' compared with CHC1 1*5 per mille defibrinated blood, 
unlaked (pig). 
Chloroform 
in ' Ringer ' 
Chloroform in Blood 
Reflexes £ 
50 ne 
Recovery 
Reflexes gone 
Recovery 
Tadpole 
E 
1 min. 40 
sees. 
3 mins. 25 sees. 
Tadpole F 
1 min. 25 sees. 
3 mins. 
F 
1 ,,25 
4 » 15 » 
E 
1 ,,15 » 
po sees, (begins) 
?» 
G 
1 „ 5° 
2 „ 
„ H 
2 „ 
I min. ,, 
?? 
H 
2 „ 10 
3 » 
„ G 
1 » 55 » 
30 sees. „ 
The solution of chloroform 1*5 per mille in blood was made by adding 20 c.c. of 5 per 
mille solution of CHC1 3 in ' modified Ringer,' to 80 c.c. of the fresh defibrinated blood. 
It is thus seen that the physiological effect of chloroform in Ringer's fluid is 
much greater than that of the same percentage of chloroform in blood. As tested on 
tadpoles, CHC1 ; in -75 per mille dilution in Ringer's fluid is as powerfully narcotic 
as twice that percentage offered, not in Ringer's fluid but in slightly diluted blood. 
Were the blood quite undiluted, the contrast would presumably be stronger still. 
