1045 
Apparently the amount of energy applied with radiation is much 
larger, but there is no saying how much of it is adsorbed by the 
muscular elements, and this, of course, is the essential thing. 
The amount of energy in the case of the normal element, potassium, 
is still more difficult of determination. The photo-chemic effect of 
potassium salts shows itself only after 56 days on the photographic 
plate and the ionizing influence upon the air is 1000 times smaller 
than that of uranium-oxide. The total radio-activity may be deduced 
from it by a round-about way with some allowance for the absorp- 
tivily. The doses of the two elements to be present in the artificial 
circulating fluids are empirically in the ratio of 53:15 mgrm. 
per litre !). 
The analogy in action, described just now of all known radio- 
active elements, of small (K and A5) as well as large (U, Th, Ra) 
atomic weight, is not restricted to the heart. The vascular endo. 
thelium is also affected by it as far as K, Rb, U, and 7h are 
concerned; likewise the striated muscles according to experiments 
performed in the last few months by Dr. GuNzBure in our laboratory. 
Furthermore the statements made by Prof. HAMBURGER and his pupil 
BRINKMAN in the previous meeting about the phenomenon that the 
epithelium of the kidney becomes permeable, when either the 
potassium- or the uranium-salt is wanting in the artificial circulating 
fluid, lend support to our view. 
Between potassium on the one hand and uranium and thoriuin 
on the other, there is, moreover another correspondence, viz. their 
relation to calcium and strontium. The first and the second group 
of these salts counteract each other, i.e. their dosage may be varied 
within certain limits, on this understanding, however, that if the 
1) The distribution of the radio-active energy supplied with the artificial circu 
lating fluid takes place in widely different ways: with the lighter elements it is 
distributed over a large number of atoms, every atom carrying only a very minule 
quantum of energy. With the heavier elements, however, it is accumulated in a 
few atoms, most of all in the case of radium. There is, therefore, much less 
chance for an atom contained in the circulating fluid to adhere to or to enter a 
muscle cell, with the heavier elements than with the lighter ones. It suffices, 
however, that some few cells are rendered automatic, for, when once begun, the 
excitability of the cardiac muscle spreads automatically; still, those few cells must 
be worked upon. We might in some way make allowance for the chance, alluded 
to here, by dividing the quanta of energy, transmitted per */j) cc, by the atomic 
weight of the carrier. This would bring out the inferiority of the energy borne by 
the heavier atoms. It really will be seen then that the energy-values for the 
various elements approximate each other (see the Table. Proc. K. A. v. Wet. 
Vol. XX p. 636), 
