There is some variety in the cupboards and tables provided in the
various laboratories, but, in general, they follow the design shown in
Fig. 13. The table tops, 12 ft. long, are of clear maple in full-length
pieces, ⅞ in. thick and 2⅝ in. wide, laid on edge and drilled at
18-in. intervals for bolts. These pieces are glued and drawn together by
the bolts, the heads of which are countersunk. The tops, planed off,
sanded, and rounded, are supported on pipe legs and frames of 1¼ by
1½-in. galvanized-iron pipe with screw flanges fitting to the floor and
top. Under the tops are drawers and above them re-agent shelves. Halfway
between the table top and the floor is a wire shelf of a frame-work of
No. 2 wire interlaced with No. 12 weave of ⅝-in. square mesh.
Certain of the tables used in the laboratory are fitted with cupboards
beneath and with drawers, and, in place of re-agent stands,
porcelain-lined sinks are sunk into them. These tables follow, in
general style and construction, the re-agent tables. The tables used in
connection with calorimeter determinations are illustrated in Fig. 14.
The sinks provided throughout these laboratories are of standard
porcelain enamel, rolled rim, 18 by 13 in., with enameled back, over a
sink and drain board, 24 in. long on the left side, though there are
variations from this type in some instances.
The plumbing includes separate lines of pipe to each hood and table; one
each for cold water, steam at from 5 to 10 lb. pressure, compressed air,
natural gas, and, in some cases, live steam at a pressure of 60 lb.
On each table is an exposed drainage system of 2½-in. galvanized-iron
pipe, in the upper surface of which holes have been bored, through which
the various apparatus drain by means of flexible connections of glass or
rubber. These pipes and the sinks, etc., discharge into main drains,
hung to the ceiling of the floor beneath. These drains are of wood,
asphaltum coated, with an inside diameter ranging from 3 to 6 in., and
at the proper grades to secure free discharge. These wooden drain-pipes
are made in short lengths, strengthened by a spiral wrapping of metal
bands, and are tested to a pressure of 40 lb. per sq. in. Angles are
turned and branches connected in 4- and 6-in. square headers.
[Illustration: Fig. 13.