largest
libraries of Boston and Cambridge, each differing from the others in age
and atmosphere. The bindings of the volumes examined bore their own
record in dates and ownership, by which the conditions of their
atmosphere in respect to gas and (approximately) to heat were made
known for periods varying from current time to over two hundred years.
In the Public Library the combined influences of gas, heat and effluvium
have wrought upon the leather until many covers were ready to drop to
pieces at a touch. The binding showed no more shrinkage than in the
other libraries, but in proportion to the time the books had been upon
the shelves the decay of the leather was about the same as in the
Athenaeum. I am informed that many of the most decayed have from time to
time been rebound, so that a full comparison cannot be made between this
and the others. In the Athenaeum less gas has been used, and there is
very little effluvium, but the mealy texture of the leather is general
among the older tenants of the shelves. Numbers of volumes in the
galleries were losing their backs, which were more or less broken off at
the joints from the shrinkage and brittleness of the leather. The plan
has been proposed of introducing the vapor of water to counteract the
effects of dryness upon the bindings. In this library the atmosphere has
the usual humidity of that out of doors, being warmed by bringing the
outer air in over pipes conveying hot water, while the other libraries
have the higher heat of steam-pipes. If, therefore, its atmosphere
differs from that of the other libraries in respect to moisture, the
variation is in the direction of greater humidity, without any
corresponding effect on the preservation of bindings. In fact, proper
ventilation and low shelves seem to be the true remedies for these
evils, or, rather, the best means of amelioration, since there is no
complete antidote to the decay common to all material things. The last
condition involves the disuse of galleries and of rooms upon more than
one flat, unless the atmosphere in the upper portions of the lower rooms
be shut off from the higher, as it should be. Another precaution which
might be taken with advantage is to use the higher shelves for cloth
bindings.

"In the Harvard College Library no gas has ever been used, nor any other
artificial illuminator to much extent. Neither had any large number of
the volumes been exposed to the products of gas-combustion, except