STORAGE OF SPECIMENS 287 



coarsest first. The sieves should be made of brass wire 

 gauze, and are more convenient if fitted with handles 

 (Fig. 158). The coarsest should have meshes about 

 J inch square, the finer patterns with eight, sixteen, and 

 thirty-two meshes to the inch. It is advisable to pre- 

 serve a sample of the ooze in alcohol, for many minute 

 organisms will pass through even the smallest of the 

 above meshes. A stream of water from a service 

 pipe may be turned into the sieve, or it may be dipped 

 repeatedly in a bucket of water. Shaking is very 

 destructive and should be avoided. 



Samples of stones, sand, mud, or ooze should always 

 be preserved ; small canvas bags are useful for this 

 purpose. 



3. For chemical and physical work little can be 

 done at sea, beyond the collection of water samples, 

 without extremely elaborate appliances. The fitting 

 up of a laboratory for immediate analysis is a matter 

 too technical for an elementary work such as the 

 present, but the Society is prepared to advise on the 

 point. If such analysis is not contemplated, the 

 chemical and physical work demands little more than 

 proper storage for bottles and apparatus, and a 

 writing-table. 



4. Storage of Specimens at Sea. — The larger and 

 rougher specimens obtained by dredge or trawl, after 

 the necessary preservation (Chapter XI.) should have 

 their label tied on to them, and then be wrapped in 

 cheese-cloth and stored in spirit or formalin. It is 

 handy to have on deck for this purpose a wooden 

 tank, lined with lead (zinc tends to pit with formalin). 

 The lid should fit on to a thick rubber flange, and be 

 held down by wedges driven under the cross-stays of 

 the tank. Trays of lath inside serve to distribute 

 the pressure of the upper layers of specimens. A 



