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always the same position, this fact can be demonstrated very clearly, 
as can also the whole process of the negative-inotropic action. 
By accumulating the irritation the process may be much increased and 
lengthened. Fatigue comes readily in consequence. To obtain an 
equally great effect each time, it is necessary to insert comparati- 
vely long intervals between the periods of irritation. The conduction 
of the negative-inotropic action within the ventricle-wall takes place 
in a way different from the motory irritation. By compressing the 
muscular wall by means of a clasp the inotropic conducting power is 
raised sooner and under lower pressure than the motory one. 
Experiments must still be made with regard to the swiftness of the 
inotropic conduction. 
The speaker illustrated his lecture by the aid of a number of 
cardiograms. 
Chemistry. — Dr. A. Smits: “Investigations with the Microma- 
nometer”, (Communicated by Prof. V. A. JULIUS). 
1. After the investigations, published under this title in Sept. 
1899 '), I have been enabled by the great kindness of Prof. BAKHUIS 
Roozes0om to continue my measurements. 
Having made some improvements in the apparatus, which might 
possibly modify the results, it seemed very desirable to me to proceed 
with the measurements; moreover I considered the question, whether 
the decrease of the molecular vapour-tension continues to increase 
with the concentration also when the solution is still more diluted, 
as so important, that in my opinion nothing should be neglected, 
which might contribute to the solution of the question. 
The improvements made were the following: 
First the manometer was made from chosen tubes, which might 
be considered as perfectly cylindrical as appeared from the calibration. 
Secondly all the taps were done away with, so that there was 
absolutely no occasion for leaks. 
Thirdly the icebath was treated with more care, by excluding it 
from the surroundings by a thick layer of wool. 
The measurements furnished the following result: 
1) Proc. Royal Acad. at Amsterdam, Vol. IL. p. 88. 
1 
Pe 
