394 TRUE AND Gries: Heavy METALS 
no diminution in the poisonous action of the corrosive sublimate 
is seen. Indeed, the mixture is markedly more poisonous than * 
the solution of the simple salt. Zinc sulphate gives a very differ- 
ent result when calcium sulphate, 7/256, is added. Whereas 
growth is much retarded in a m/81g2 solution of zinc sulphate, 
in the mixture at /2048 growth is more than twice as rapid 
as in the control grown in water. We have here a very marked 
stimulation in the growth-rate, resulting from the addition of the 
lighter metal to the zinc. 
When to salts of the heavy metals compounds of the lighter 
TaBLe IV 
Mrxep Sotutions, HEAVY METAL AND LIGHT METAL. DIFFERENT ANIONS. 
AVERAGE GROWTH-RATES IN MILLIMETERS 
So 
Concent. of CuSO,. CuSO, Cu(CH,CO,), HgCl, CuSO, 
Solution of de Bi As 4 
Heavy CaCl, CaCl, Ca(NOs)> Ca(NO,)> Urea 
Metal m2|x28 /128(dup. ) m|32 m|32 ml64 
m| 4096 0.0 
m/|81g92 2.0 1.0 
m/16384 1.5 3.0 5.0 6.0 
m|32768 3.0 4.0 9.5 16.0 0.0 
m/65536 7.0 10.0 0.5 
m1 31072 16.5 4-5 
Check 12.0 15.5 13.0 ie 140 11.5 
—— 
metals are added, in the form of salts in which the anion differs 
from that in the copper compound, a condition of things is found 
which is not essentially different from that just cited. In Table 
IV results bearing on this point are presented. 
It will be noted that when calcium chloride, 7/128, is added 
TABLE V 
MIXED SOLUTION. CoppER SULPHATE WITH CANE SUGAR. AVERAGE GROWTH- 
RATES IN MILLIMETERS 
Concent.of | Cane 
Cane | Cane Cane | Cane | Cane Check 
Copper | Sugar | Sugar Sugar | Sugar | Sugar | Sugar | | in 
Solution | ashe m eee alg Be | tee | WO 
} PN SING oy Pe OG a Re ENOL CRM ee ee eae Sine cisco Seana nar 
| } | | 
mi65536 | 9.0 | 27 che Le Cie ee 
to copper sulphate, a marked diminution in the poisonous action 
of the copper compound takes place to a degree equal to that 
seen when the anions are similar. When to copper acetate cal- 
