Evening star., 1938-02-27
NEW CARRIERS FOR LIBRARY

via the pneumatic tube).
The book has now been placed upon
the rack of the carrier, where it is
automatically picked up by the con-
stantly moving machinery and deliv-
cred to our desk in the reading room.
These carriers are fascinating to OBJ
serve. They consist of pair of par
allel endless sprocket chains about
2012 inches apart and run ceaselessly
during the day by a small electric
motor at l00foot-per-minute speed.
Suspended on trunnions between the
chains. the book trays may pass freely
over the axles at the many direction
changes en- route. This is possible
because of the size of the sheaves over
which the sprocket chains run The
carriers route is entirely in vertical
manner, from the overhead sheaves 8
feet above the reading room floor at
the desk there, vertically downward
to the cellar. then horizontally below
the ceiling to the center Of the book
stack where it again follows the ver-
tical plane upward. passing through
all the stories COR decks) to the top Of
the stack to pair of sprocket sheaves
| there, and then back to the reading
room by parallel route.
Eighteen equidistant aluminium book
trays are suspended to the chains
and room for more if necessary. These
trays have bases that consist Of a
horizontal set of parallel brass fingers
that are turned up slightly at the tips.
much like a garden broom-rake, to
keep the books and trays from slipping
off or projecting over. The tray
passes through similar fat-toothed
racks that are located at the terminal
station in the reading room and also
at each stack deck. When the tray
arrives at the delivery station the book
is 'combed" off and slides into a softly
padded box.
THERE are 10 movable spurs on the
back of the travelling tray which
secure its automatic action. one for
each of the nine stack-deck stations
and one general key. A dial Is set by
hand when book is taken on. which
prevents the tray from responding to
any other signal until the book has
been delivered. At one time it was
customary to return books to their
proper stacks by the carriers. This
proved impractical, so today the books
are sorted, then loaded on trucks for
their respective stacks.
Just as we have dial telephones, so
will the new carriers in the new annex
building have dial system. which will
eliminate the present hand-setting
method Of controlling the carrier. An
example would be: "A" wishes to send
a shipment of books to "B," who is on
deck g. "a" dials and the carrier
goes on its route. ignoring all other
signals until 1t has delivered the ship
ment to "B" on deck 2. It will then
automatically reset itself as it proceeds
on its way, travelling at speed of 60
feet per minute
Flexible operation OF the carrier
makes it possible to send books simul-
taneously, e.g., from decks, 2. 9 and IL
to deck 8, and at the same time from
deck to each Of those decks 1t may
also be noted that all transporting
equipment is designed to keep the back
of the book and its shelf number con-
tinually in view.
| Just under the reading room will
be two control rooms that will operate
as one. To this main control room
are sent all books from the decks
below, where they will be transported
by silent carriers directly to the book
issue desks of the reading rooms So
it is with books returned by readers.
They will be sent first to this main
control room, sorted and sent to their
proper decks. The main control room
is also the terminus for the unique
pneumatic carrier system connecting
the annex with the main building.
THE oval leather pouches that re-
mind one of duffle bags have a
capacity Of eight average size octave
volumes. They travel at a speed Of
IS feet second and arrive in q bank
Of air that acts as a cushion, thus
protecting their contents. The dis
tance between the two buildings is
700 feet, which the carrier will nego-
tiate In % seconds, or less than half
minute. Deliveries of oversize books
will be made via the electric trans
that operate in the tunnel connecting
the two buildings. Another main con-
troll room in the main building under
the reading room will operate similar
| ly to that in the annex, as terminus
both for the pneumatic carrier to the
annex and for the mechanical car
riers and pneumatic tubes that might
otherwise disturb the quiet Of the
reading room. The only connection
with the latter will be by means Of .
silent continuous conveyor and . tube
for call slip exchanges and messages.
For those who are wondering where
the annex building Is located. It u
just behind the main building and In
the same portion of ground as that
occupied by the Folger Shapkespears
Library. It is interesting to know
that by the removal to the annex Of
several divisions $4,000 shelves will
be released for other uses.
How many know that while one u
driving along from the Capitol Build.
ing to the Congressional Library ship
ments of books are travelling beneath
them in the carrier that connects the
two buildings by means Of an under
ground tunnel. This Capitol carrier
consists of small flexible, endless
wire cable that runs over sheaves at
both ends Of the route. (They were
once propelled by means Of donkey.
sngine,)