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The amount of cleaning desirable has often been discussed, and the 
statement has been made that specimens don’t “look old” when they have 
been cleaned. It is felt that specimens should appear as nearly as possible 
as they would if they had just left the owner’s hands; that is to say, they 
should be in the condition in which the Indian himself would have kept 
them, were he making use of them. There are times, of course, w T hen this 
is not a practicable goal to aim at, and one should at all times be guided 
by the actual situation confronting one and not by any theoretical standard. 
In cleaning, as in all other processes, it is well to remember that one 
must proceed with the utmost care in all cases. Such precautions may 
appear unnecessary when handling a series of some dozens, let us say, of 
arrow-points, but the careful habits of work induced by a rigid adherence 
to this rule stand one in good stead when working with rarer and more 
important material. A valuable motto is “treat every specimen as though 
it were the only one of its kind in the world,” and you may be sure that in 
a good many cases it actually is. 
PRESERVATION IN THE LABORATORY 
When one brings to mind the many hundreds of materials and pro- 
cesses which have been proposed and employed in the preservation of 
antiquities, it is somewhat breath-taking, but very consoling, to discover 
that 90 per cent of one’s troubles can be overcome by the magic formula 
“Celluloid in Acetone.” It is literally true that there is no material of 
greater value to the anthropological preparator. As a safe and easy 
routine treatment, it has everything to recommend it, bearing always in 
mind that routine treatments can only be used when the nature of the 
specimen is already well known. This preparation was first brought 
definitely to the attention of the museum world by Mr. A. Lucas, who 
was responsible for much of the work of cleaning and preserving the speci- 
mens discovered in the tomb of King Tut-Ankh-Amen, and it has been 
adopted very widely since. It may be used for impregnating porous 
materials that are in need of strengthening; as a waterproof, air-tight 
varnish; or as a strong but semi-flexible cement, merely by varying the 
proportion of acetone in which the celluloid is dissolved. 
Its preparation is simple and the ingredients inexpensive. Colourless 
sheet celluloid is cut into small pieces with scissors ; pieces about an inch long 
and a quarter of an inch wide are satisfactory. A handful of these pieces is 
put in a quart bottle, a funnel being used as a hopper. Refractory bits 
can generally be forced in with a pencil, if they are not fed into the hopper 
too quickly. The bottle is then filled about three-quarters full with acetone 
and shaken vigorously and immediately. The mass of wet celluloid must 
be broken up as quickly and as thoroughly as possible, otherwise it will 
take a long time to dissolve. The bottle should be shaken fairly continu- 
ously for ten or fifteen minutes and may then be allowed to stand for half 
an hour. It is then tightly corked, turned upside down, supported in some 
way, and allowed to stand for another half hour. By now the celluloid will 
have formed a thick mass which coils and loops down through the acetone 
when the bottle is turned over. This process of reversing the bottle at 
intervals should be continued as long as convenient or until the celluloid 
is thoroughly dissolved and the solution of equal consistency throughout. 
