46 PREPARATION AND MOUNTING 
made by dissolving gum dammar in benzole, and adding 
about one-third of gold size: it dries very readily, and is 
especially useful when mounting objects in fluid, taking care 
that no moisture extends beyond the covering glass, which 
would prevent the complete adhesion of the cement. In 
those cases where glycerine is employed as the mounting 
medium, a ring of liquid glue put round the cover first, and 
when that is dry, a second coat of gum dammar will keep 
the cover very secure, and no leakage take place. 
Liquip GLvE is another of these cements, which is made 
by dissolving gum shellac in naphtha in such quantity that 
it may be of the required consistency. This cement appears 
to me almost worthless in ordinary work, as its adherence 
can never be relied upon; but it is so often used and recom- 
mended that an enumeration of cements might be deemed 
incomplete without it. Hven when employed simply for 
varnishing the outside of the glass covers, for appearance’s 
sake alone, it invariably chips. Where, however, oil is used 
as a preservative liquid, it serves very well to attach the 
thin glass; but when this is accomplished, another varnish 
less liable to chip must always be laid upon it. (See 
Chapter V.) Yet it makes excellent cells. 
Buiack Japan.—This is prepared from oil of turpentine, 
linseed oil, amber, gum anime, and asphalt. It is trouble- 
some to make, and therefore it is much better to procure it 
at the shops. It is a really good cement, and serves very 
well to make shallow cells for liquids, as will be described in 
Chapter IV. ‘The finished cell should be exposed for a 
short time to the heat of what is usually termed a “cool 
oven.” This renders it very durable, and many very careful 
manipulators use it for their preparations. 
ELECTRICAL CEMENT.—This will be found very good for 
some purposes hereinafter described. To make it, melt 
together— 
5 parts of resin. 
1 » beeswax. 
1 » red ochre. 
