( 640 ) 
meter, I did not notice a minimum of the molecular diminution 
of vapourpressure; it is possible that the cause of this is as 
follows: 
At about 100°, I observed a minimum at the concentration of 
0.5 gr. mol.; should the position of this minimum alter with the 
temperature which is quite possible, it may occur that at lower 
temperatures it is displaced in the direction of still more dilute so- 
lutions and that at 0° it may fall below the concentrations with 
which I was able to make sufficiently accurate observations. 
To decide whether there really is a minimum which changes its 
position with the temperature, I propose to make further measure- 
ments of the diminution of vapourpressure of solutions at tempe- 
ratures between 0° and 100°. 
Amsterdam, University Chem. Laboratory. 
April 1900. 
Physiology. — “Some reflexes on the respiration in connection 
with LABORDE's method to restore, by rhythmical traction of 
the tongue, the respiration suppressed in narcosis”. By 
M. A. vaN Merve (Communicated by Prof. C. WINKLER). 
In the Weekblad van het Nederlandsch Tijdschrift voor Genees- 
kunde, March 31, 1900. Dr. WeENCKEBACH inserts a note on LABORDE's 
communications in the Académie de Médecine, which are published 
in the Bulletins de U Académie de Médecine, N°. 45 1899 en N°. 2, 
4 5, 6. 1900 and with slight modifications in the Comptes hendus 
de la Societé de Biologie: 1899. N°. 39 and N°. 2, 4, 5. 1900. 
In this communication LABORDE gives fuller details about a method 
in which rhythmical traction of the tongue is used to restore the 
paralyzed respiration. An explanation is to be found for this 
phenomenon, as it cannot be considered as anything but a re- 
flectory action, originating from the sensible nerves of the first air- 
passages on the so-called centres of respiration. LABORDE thinks, 
that according to his experiments the reflectory action depends on 
the Nn. laryngei superiores, the electrical and mechanical excitation 
of which brings about an “arrest” during the active respiration, 
whereas it restores the respiration when the latter was suppressed. 
In the laboratory of Prof. WINKLER, under whose guidance im- 
portant investigations on the mechanism of the respiration have been 
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