No. 421.] MUSEUM TECHNIQUE. 59 
would perhaps be best to give them a coat of ox gall, which is used 
in painting on glass. The pupil should be colored a bluish black 
. and surrounded with a golden circle verging into the iris; to the iris 
one can reproduce the niceties of its natural appearance, namely, its 
silver or gold glint, red circles and spots, black stripes, dots, etc.’ 
As soon as the paint is dry the eye should be moistened; otherwise 
it would sink, though a little sinking is hardly noticeable when the 
fish is put in alcohol. 
Injured fins must be repaired before painting, which may be done 
by pasting on underside small pieces of silk paper with a thin solu- 
tion of gelatin. The repaired places must be carefully dried before 
painting. 
(3) The fastening of the fish in the glass. 
_ The glasses used in our museum are blown oblong, with parallel 
walls. There are three special sizes produced by the glass factories 
of Gundlach & Miiller of Altona-Ottensen. Their comparative sizes 
in centimeters and their prices, with 5 per cent discount, are as 
follows : 
LENGTH. HEIGHT. DEPTH. PRicE. 
35 20 9 8 marks 
50 25 II ER n 
70 30 14 "M. ” 
These glasses are unground: those with polished face are more expen- 
sive, but appear also much more elegant. The firm already mentioned has 
filled many orders for such glasses, and has of course much experience. 
Transportation of the same, even of the largest glass boxes, has been suc- 
cessfully made to America without material loss. 
These glass boxes are closed with sheets of glass about 3 mm. 
thick and the edges ground to correspond to the thickness of the 
walls of the box, to which they are securely fastened with gelatin. 
The closing of glass boxes, especially the larger ones, is not easy. 
When the collection is to stand some time undisturbed it is well to close the 
larger ones by simply covering with the glass lid. As the alcohol slowly 
evaporates it may be replaced. To open the glass boxes which have been 
closed with gelatin, it is better to cover the lid with layers of blotting paper 
and these with a wet cloth. After some time, say over night, the gelatin is 
softened, and the cover can be released with a little care. 
In order to fasten the fish in a horizontal position in the glass 
case, it should first be laid on its broad side in the manner in which - 
it is to be fastened in the glass. The tail should be supported with 
a piece of cork, or something of the kind, which is covered with 
