552 
MR. J. PRIESTLEY ON THE PHYSIOLOGICAL ACTION OE VANADIUM. 
Exp. LXXX.— May 13, 1874. 
Rabbit (buck). — Weight 1958 grms. 
Dose 5 cub. centims. of the 5 per cent, solution (250 milli- 
grammes V 2 0 5 ), injected under the skin. 
Note. — The half of this experiment which refers to the circulation has already 
been given on p. 524 (Exp. XLV.) with full explanatory remarks ; 
similarly the half referring to the respiration is found on p. 537 
(Exp. LVI.). 
From the data furnished by those experiments a Table (fig. 5, Plate 46) has been con- 
structed illustrating the simultaneous effects of the poison upon the vasomotor and 
respiratory centres. The chief points of interest are : — (1) that the line of mean blood- 
pressure sinks from beginning to end, while the line indicating the rapidity of respira- 
tion first of all rises and afterwards sinks ; and (2) the numerous irregularities, especially 
near the termination, indicating the successive revivals of functional activity on the 
part of those centres. 
Exp. LXXXI.— June 15, 1874. 
Rabbit. — Weight 2430 grms. 
Dose 1 cub. centim. of the 5 per cent, solution (50 milligrammes 
V 2 0 5 ), injected into right external jugular vein. 
Note. — ’The half of this experiment which refers to the circulation has already 
been given on p. 527 (Exp. XLYII.) with full explanatory remarks; 
similarly the half referring to respiration is found on p. 538 (Exp. LVIII.). 
The results of this experiment are tabulated in the manner adopted in the last 
experiment (fig. 6, Plate 46). The remarks there made apply to this Table also, except 
that the initial increase in rapidity of respiration is in this case more marked ; and 
when once the rapidity has commenced to diminish it does not, as in the preceding 
experiment, ever increase again. This may, however, have been due to an error in the 
method of observation (see note to fig. 6, Plate 46). 
Resume of the Action of Vanadium upon the Muscular and Nervous Systems. 
In the account of the general action of vanadium upon the animal economy it was 
noticed that in nearly all animals, when the dose was large, one of the most important 
symptoms of poisoning was the occurrence of convulsions and paralysis of motion. 
The experiments which have just been detailed furnish the explanation of those 
phenomena. 
Frogs were the animals chiefly used. As, however, paralysis was the only form which 
