33 
A NEW PLASTER-SPREADING APPARATUS. 
DEVISED BY WILLIAM MARTINDALE, 
DISPENSER, AND TEACHER OE PHARMACY TO THE UNIVERSITY COLLEGE HOSPITAL. 
This apparatus consists of a trough with a false bottom, in which a series of 
jets from a Bunsen’s burner are applied to heat the side plates, the cloth being 
passed under these to be covered with a layer of plaster. 
aa. The “ cheeks ” or ends of the machine. 
b and c. The side-plates of the trough. 
d. The roll of cloth. 
e. The support for the cloth and plates. 
ff. The screws to regulate the front plate b. 
gg. The nuts in which they work. 
hh. The heads of the screws. 
ii. Two threadless nuts. 
The framework of the machine, made of cast-iron, has two “cheeks” (aa) 
placed at right angles with the bottom. These cheeks form the ends of the 
trough. The interior of each has two grooves in which two wrought-iron plates 
(b and c ) fit so as to allow of their being raised or lowered as required. The 
grooves of the back plate (c) are at an angle of 60° with the bottom, and in 
them the plate works of its own free gravity. The grooves of the front plate (b) are 
at an angle of 75°. The “ play ” of this plate is regulated as will be described. 
The edges of the plates at the bottom where they press upon the cloth are slightly 
bevelled. These two plates and the cheeks above mentioned form the sides 
and ends of the trough ; the cloth ( d ) forms the bottom, as it passes through over 
an iron support ( e ). This support is in the shape of the section of a wedge, the 
acute end of which is terminated by an arc. The arc forms its upper surface 
over which the cloth is drawn ; the support, as is shown in the figure, projects a 
VOL. XI. D 
JcJc. The levers. 
II Two moveable weights. 
m. The spread plaster. 
n. A roller on which the cloth is placed, 
oo. Two rests for this roller. 
p. The heating apparatus. 
qqq. Its two branches. 
