DEEP-SEA EXPLOEATION. 
407 
turned aside from time to time while tlie more delicate forms are picked from the 
surface of the mass or from the meshes of the sieve. 
After the specimens resulting from the haul arc gathered from net and sieve they 
are taken to the laboratory for assorting and preservation, a process usually quite 
simple, yet requiring experience and good judgmeut. 
Alcohol is the preserving medium heretofore in general use. To insure its 
successful application, most specimens require to be first placed in a weak solution 
which, as it permeates tlie tissues, should be changed to stronger, thus completing 
the i)reserving process before they have time to soften and decay. An alcoholic 
mixture of 75 per cent is regarded as sufficient for the permanent preservation of 
well-(!ured specimens, although some require a stronger Iluid, while others are e(]ually 
well preserved in a weaker solution. 
The necessity for a weak preliminary bath is illustrated in the case of a large fish 
of firm texture, which if thrown into strong, warm alcohol will quickly harden on 
the exterior, thus excluding the preserving fluid from the inner tissues and causing 
them to soften and decay. On the other hand, if it is subjected to a weak mixture of 
35 to 50 per cent of cool alcohol, the fluid will penetrate the whole structure, aftei' 
which the strength may be safely increased as desired. 
The condition of alcoholic specimens collected in hot climates depends to a^ certain 
degree upon the temperature of the i)reservative when it is applied, a fact which has 
not always been given due consideration. The simple reduction of the alcoholic 
mixture by the addition of water raises its tem])erature from 10° to 20'3, which, added 
to the constant heat of the surrounding atmosphere, greatly increases the difficulties 
attending the process of preservation. 
Mr. James E. Benedict, when resident naturalist of t\iQ Albatross^ adopted the phui 
of cooling ailcoholic mixtures actually in use in the tropics by surrounding the tanks 
with ice, and as a further precaution he placed very delicate s])eciniens in the cold 
room while they were absorbing the preservative, the cooling process being attended 
with excellent results. 
TO pkeserve fish. 
Wash them in clean water, and if more than half a pound in weight make an 
incision on the right side, just above the middle of tlie belly, to admit alcohol freely 
into the body cavity— the position of the cut leaves the left side intact iii case a drawing 
or xihotograph should be required — then lay them out in dishes or pans of weak alcohol. 
After soaking a sufficient time, use the hypodermic syringe freely, if the body cavity 
has not been cut, injecting 05 per cent alcohol; then wipe carefully, wrap them in 
cheese-cloth, and pack them in jars or tanks containing alcohol of sufficient strength to 
maintain it permanently at 75 per cent. The soft and spongy tissues of deep-sea tish are 
rapidly permeated by the preserving tluid, and if full-strength alcohol is injected into 
the intestinal canal and body cavity it will rarely be necessary to make an incision. 
Specimens designed for exhibition should be hardened slowly and retained in a 
natural position during the process, Avhich may easily be done by securing tliem to a. 
woven-Avire screen of about half an inch mesh, seizing soft pine blocks under the 
exiAanded fins. In the preparation of specimens for this purpose it is Avell to remember 
that the nearer the temperature of the alcoholic solution approaches to 40° F. (the 
point at Avhich decay of animal tissue is arrested) the Aveaker the first bath may be 
made, 25 per cent or even less being alloAvable, thus advantageously ]»rolouging the 
hardening [irocess, Avhich in any event can not be delayed more than a few hours. 
