Action of Calevum upon the Inhibitory Effect of Magneseum. 261 
By subcutaneous injections of a magnesium salt (for instance, Epsom 
salt—about 7 cc. of a 25-per-cent. solution per kilogramme) rabbits are 
brought to a profound state of anesthesia and paralysis. The slow and 
shallow respirations indicate the approaching danger. Now 6 or 8 ce. of 
an M/6 or an M/8 solution of a calcium salt are given through the ear vein. 
Within a few seconds the respiration becomes quicker and deeper, and within 
one minute the animal turns over, sits up, and appears normai. 
Here calcium not only did not add an inhibitory effect, but completely 
neutralised the profound inhibitory effect of magnesium. The companionship 
of calcium and magnesium within the body means, at least in many 
instances, not a concerted action of similar effects, but rather a resultant 
effect of antagonistic actions. 
We may add that the experiment calls to mind similar relations existing 
in plant physiology ; the retardation of growth on account of the presence of 
too much magnesium in the soil is promptly corrected by the addition of a 
calcium salt; the process is termed “liming.” In animals, therefore, as well 
as in plants, calcium is antagonistic to magnesium. 
