The doses are stated in terms of milligrams
of bismuth metal per kilo, injected, of course, in
the form of bismuth sodium tartrate; the small doses
mentioned were in all cases the first injections in
the experiments, and the injections have been made
over approximately the same length of time. From,
the manner in which the experiments were conducted,
nearly all the large doses followed on a previous
smaller 'one and thus the relation with them between
dose and effect is not strictly accurate.
Minimum, and maximum doses which produced changes in
the heart, and blood pressure:
0.45 to 0.54 mgs. bismuth metal per kilo, gave
a slight fall in blood pressure and lessening of the
amplitude, and slowing, of the heart.
1.54 to 1.78 mgs. bismuth metal per kilo, gave
a marked fall in blood pressure and marked lessening
of amplitude, irregularity and slowing of the heart,
and if repeated in the course of the experiment,
gave more pronounced slowing, lessening of amplitude
and death of the heart.
2.67 mgs. bismuth metal per kilo, gave marked
irregularity, lessening of amplitude and temporary
stopping of the heart.
Reference to the determination of the lethal
dose of bismuth in cats shows that the minimum fatal
dose is ten times the minimum dose which gives slight
changes in the heart and blood pressure.