400 
JOHN FAUST. 
dog - , io.o to 25.0 grms.; sheep and goat, 20.0 to 25.0 grms.; 
cattle, 50.0 to 75.0 grms.; horse, 500.0 to 75 °-° g rms * Even 
the symptoms for chronic lead poisoning are different for cat¬ 
tle or horse. In the former we find marked disturbances of 
the alimentary tract, which are entirely absent in the horse, 
this latter showing asphyxia. 
Mercury is medicinally used in two very different types 
o c chemical combination, besides its application as such, finely 
disintegrated with some fat, in the form of gray mercury oint¬ 
ment. Cattle are exceedingly susceptible to the influence of 
this latter, while horses and dogs are exceedingly tolerant to 
it. While 30.0 grms. of gray ointment may cause grave toxic 
appearances on cattle, we have cases on record, one of a dog 
which swallowed 170.0 grms. at once without grave disturb¬ 
ances following, and of a horse which died only after 3240.0 
grms. (more than three kilos.) had been applied within a 
month. Birds, on the other hand show great susceptibility. 
Of the two different types of chemical combinations, the 
most poisonous is the mercuric chlorid (corrosive sublimate, 
Hg Cl,), used as an antisepticum in surgery, etc. Here, 
also, cattle show decidedly greater susceptibility than horses. 
The fatal dose for cattle is 4.0 to 8.0 grms.; for the horse, 8.0 
to 10.0 grms. For calomel (mercurous chlorid, Hg 2 Cl 2 ), 
which is of much weaker toxic action, the relations are simi¬ 
lar. While cattle suffer severely after 8.0 to 10.0 grms., 
horses will begin to do so after 20.0 grms. 
But we have also a chemical compound for which these 
relations are reversed. This is tartar emetic. Horses may 
be called the most sensitive towards this substance ; they will 
averagely die after 15.0 to 30.0 grms. Cattle, on the other 
hand, will not even show signs of a reaction after doses of 
50.0 grms. had been administered. 
ISOLATION OF TUBERCULOUS CATTLE BY SEPARATION.* 
By John Faust, Poughkeepsie, N. Y. 
The closing remarks of my paper last year on tubercu¬ 
losis were, if we cannot get the aid of the Government, or 
* Read at the meeting of the U. S. V. M. A., at Des Moines. 
