go The Botanical Gazette. {March, 
as the screw, and fits into an iron piece, seven-eighths inch 
square and three-eighths inch thick, that has first been slightly 
hollowed with a five-eighths inch drill to form an oil cup, and 
then countersunk to receive the point of the core. 
The construction of the frame which holds the shaft and 
pulley is made sufficiently clear by the figures of plate IX and 
by details 2, 6, cand d of plate X. The steps in the con- 
struction of the shaft and pulleys, however, need to be given. 
A pine stick 2x2 inches is sawed the proper length for the 
shaft; the centers of the ends are determined by crossing di- 
agonals from the four corners; holes are bored in the center, and 
the steel cores are driven in, the upper flush with the surface and 
the lower protruding five-eighths ofaninch. The stick is then 
fastened in the lathe by grasping the end of the lower core in 
the lathe chuck and bringing the dead center of the lathe 
into the depression countersunk in the upper core. The ulti- 
mate diameter of the shaft is to be one and one-half inches. 
The stick is now turned to a diameter slightly larger than this; 
a block is cut two and three-fourths inches square from two 
inch stuff; a hole one and one-half inches in diameter is bored 
through its center, and then the shaft is carefully trimmed 
with the turning gouge, or brought down with coarse sand 
paper until the block can be crowded on firmly. Then the 
block, in position flush with the end of the shaft, is turned to 
two and one-half inches in diameter. Then beginning three- 
fourths of an inch from what is to be its lower face the block 
is tapered down to the diameter of the shaft as shown in plate 
IX, figure 5, 6. The upper face is made slightly concave, and 
a V-shaped groove is turned on the edge for the belt. 
The pulley is now to be taken off, and after applying glue 
evenly over the space to be occupied on the shaft it is crowde 
into its position again. It is advised that the pulley be 
turned in position before gluing as above described because 
of the possibility of the block chipping too deeply while 
roughing off. 
To make the large pulley, two pieces slightly over seven- 
teen inches square are cut from one-half inch boards 
and screwed together with the grains crossing to prevent 
warping; the two surfaces are dressed true; the center is de- 
termined by crossing the diagonals; a circle is marked out 
from the center seventeen inches in diameter, and a one and 
one-half inch hole is bored through the center to fit the shaft. 
