METHODS OF PREPARING FISHES FOR EXHIBIT. 1 36 1 



Take the mold from the case, and, by sUght manipulation, the specimen is 

 removed without damage to either. Thoroughly work talcum powder into the 

 mold, with a soft brush, to remove the oily surface, and immerse in a 5 per cent 

 solution of formalin (measuring the latter as if 100 per cent) for five minutes. 

 The surface of the glue is thus hardened, and only requires a few minutes in 

 water, heated to a temperature of about 100° F., to prevent a too sudden chilling 

 of the wax. Remove the excess of water with a soft sponge, and, after quickly 

 applying a very thin coat of oil, the mold is ready for filling. 



The transparency of the specimen must govern the composition of the wax 

 for casting, but the following formula will prove generally useful. Melt in the 

 double boiler one pound of paraffin to four pounds of bleached beeswax, to 

 which add one teaspoonful of Canada balsam, or Venetian turpentine, to each 

 pound of wax. Color with oil, tube colors, to the lightest tint of the ground 

 color of the specimen. 



As the fins and tails of fishes need strengthening, fill the mold and, after 

 allowing it to stand a minute or two, empty it of all the wax except the thin film 

 which will have formed over the surface, and while still hot press a single thick- 

 ness of bolting cloth along the fins and tail; also add a silk covered wire at the 

 spines, dashing a small quantity of wax over all to keep in position, when the 

 mold should be again filled. The entire cast may be given additional strength 

 by applying one or two coats of the cloth over the entire surface. 



The principal care to be exercised in this work is in the flowing of the wax. 

 There should be no splashing and the stream should be steady and constant, 

 otherwise "water marks" and other possible defects will result. 



Haste to remove the cast from the mold should be avoided, and under no 

 circumstances should artificial means for cooling be employed, but the mold 

 should be allowed to stand undisturbed until the wax is cold. 



In pouring the wax into molds that present deep depressions or offsets, 

 it is often necessary to resort to tilting or rolling the mold to insure the proper 

 filling, and this should be done as the wax is deposited. It is advisable after 

 such a mold is full to pour out a part of the wax and turn the mold at various 

 angles to remove possible air bubbles, after which it is refilled. 



In most instances the mold is easily taken from about the cast; but when 

 deep undercuts are present the glue can be removed by cutting away in small 

 sections or, more often, by merely splitting down the center. This is recom- 

 mended where there are delicate parts which need care. A saving of material 

 may be accomplished by inserting a rough form of wood and filling the inter- 

 vening space with melted wax. 



With fishes presenting a strong contrast of color, excellent results are 

 obtained by tinting wax the several colors represented and applying each 

 in its relative position with a soft brush. To do this properly, the mold must 



