314 Prof. Horsford on the Permeability of Metals to Mercury. 
I. Is the specific gravity increased by being saturated with 
mercury. 
he experiment was made with tin before it began to crys- 
tallize, and after the crystallization had apparently come to an end. 
Spec. gr. of pure tin employed in the experiment, 7:29 
Tin saturated with mercury, , ‘ ; , 7:50 
Tin and mercury—crystallized amalgam, SO 
Il. What is the velocity of transmission of mercury through tin? 
The bars used in the following experiments were cast in paper 
moulds surrounded by dry sand. A bar 0:0U6 mm. in diameter 
was placed in mercury having 0-185 mm. above the surface of 
the liquid metal. The mercury ascended as follows— 
In the Ist day, ‘ ‘ 0:010 mm. 
66 2d, “ce ‘ . : 0-010 6b 
st. 3d “ = 0-010 tc 
«© 4th and 5th days, ‘ ez; 0A O22. # 
Grol oGeh, day, ‘ ‘ 
vey e 8th, ‘ : . 
At the end of six days the bar began to crack open at the bot- 
tom. In fifteen days the mercury reached the top of the bar, 
0-185 mi.—making for the last seven days, a velocity of 0-0137 
mm. per day. 
The movement of the mercury in tin differs greatly from that 
of lead. In the latter this progress is by a sort of inverse geo- 
brite ratio, in the former it is remarkably uniform. 
eury continued to rise, through several days, and attained a total 
increased elevation of 0217mm. Before the mercury had en- 
tirely ceased to ascend, the bar below opened into numerous fis- 
sures, and the entire column of amalgam became eminently brittle. 
__t would seem as if the crystallization arrested the play of affin- 
ities upon which the ascent of the mercury depended. 
Ill. Does the tin permit the syphon action ? 
A bar of 0-006 mm. diameter, 0-185 mm. total length, was bent 
into syphon form and the shorter division placed in mercury. In 
0 
more the bar broke of its own weight. The brittleness of the 
saturated tin bar, taken in connection with the more rapid crys 
tallization, made it impossible to perform the serial experiments 
d. 
IV. Does mercury saturated with lead flow through tin bars ? 
A syphon of 0:170 mm. total length was placed in a cup con- 
taining mercury that had run through lead. In due time the 
