304 BOTANICAL GAZETTE [APRIL 
My instrument is illustrated in the three accompanying figures. It 
consists essentially of the works of a powerful American eight-day 
clock, geared to a revolution in fifteen minutes, inclosed in a practically 
dust- and moisture-tight metal case, capable of being used in any desired 
position. Used vertically (fg. 7) it stands upon three leveling-legs 
and carries a disk with a rim holding 
a 4-inch pot saucer (to take up leakage 
from the pot), in which may be set any 
size of pot up to 5-inch, though in this 
position it will carry a still heavier pot. 
‘In this figure may also be seen, on the 
left of the spindle, the nut by which the 
works are started or stopped, and the 
covers of the winding-holes. It can, 
of course, be wound without disturbing 
the plant. Used horizontally (fg. 2) 
it may, by means of the perforated 
screw posts and clamping-screws on the 
back of the case, be fixed at any desired 
height on the vertical rod of any com- 
mon laboratory support. The spindle 
rod, either carrying a plant attached by 
Fic. 2. 
