9 8 



Society for Experimental Biology and Medicine. 



67 (210) 



The effect of nephrectomy upon the toxicity of magnesium sul- 

 phate when given by mouth. — A demonstration. 



By S. J. MELTZER. 



[Fro m the Rockefeller Institute for Medical Research.] 



Three rabbits were shown, one normal and two nephrectomized. 

 The nephrectomy was performed nine hours before the demon- 

 stration. One nephrectomized animal received by mouth, soon 

 after the nephrectomy, magnesium sulphate (6 grams per kilo in a 

 25 per cent, solution). The normal animal received by mouth 7 

 grams per kilo of the same salt. The other nephrectomized rabbit 

 received no magnesium sulphate. At the time of the demonstra- 

 tion the nephrectomized rabbit which had received the salts was 

 under profound anesthesia with complete muscular relaxation, while 

 the other two animals were in an apparently normal state. This 

 shows that in nephrectomized rabbits magnesium salts produce a 

 profound general effect even when given by mouth, and that the 

 absence of such an effect in the usual administratio?i of the salts is due 

 to the comparatively prompt elimination through the kidneys of a large 

 part of the absorbed salts, thus preventing at any given time the 

 accumulation within the organism of a quantity equal to a toxic dose. 



68 (211) 



Observations on a rabbit for thirty months after the removal 

 of the superior cervical ganglion. 

 By S. J. MELTZER. 



[From the Rockefeller Institute for Medical Research.] 



Langendorff 1 reported that in one experiment on a cat one 

 hundred and five days after the removal of the superior cervical 

 ganglion, the paralytic symptoms of the eye disappeared, and 

 stimulation of the cervical sympathetic nerve caused the typical 

 effects. Microscopically no nerve cells could be detected, and 

 Langendorff assumed that there was a union between the pre- 

 ganglionic and postganglionic nerve fibers. Langley, 2 on the other 



1 Langendorff : Centralblatt fur Physiologie, xv, 483, 1901. The number of 

 clays is quoted here from Langley and Anderson ; it is not mentioned in the Centralblatt. 

 'Langley : Journal of Physiology, xxv, 417, 1900. 



