33 
MICROSCOPICAL SECTION. 
December 17th, 1860. 
Letters were read from Sir Leopold Me. Clintock, Mr. J. 
W. Read, of the Admiralty, and Dr. YVallich, who accom- 
panied the former in the Bull Dog, in the late expedition to 
the North Seas. Dr. YVallich kindly presented to the Section 
a few copies of his pamphlet on “ Life in the Deep Sea,” now 
circulating amongst the members. 
A Letter was also read from Captain M. F. Maury, of the 
U.S. Navy, promising to supply envelopes for soundings 
amongst the sperm whalers and other vessels trading to the 
Pacific Ocean, &c. 
Specimens of incrustations from the boilers of the steamer 
Edinburgh, trading from Glasgow and Liverpool to New 
York ; from the steamer Rhone, from Liverpool to Venice, 
Trieste, &c. ; and from the steamer Minho , from Liverpool to 
Lisbon and Oporto, were received from Mr. W. A. Dayman, 
of Liverpool. The incrustations are as hard as marble, 
breaking with a crystalline fracture, and showing, by dift’erent 
coloured strata, the crust obtained from harbours and from 
the open sea. Mr. Dale stated that the component parts of 
the incrustations are sulphates of lime, magnesia, &c. ; he 
recommended maceration in bicarbonate of ammonia to obtain 
calcareous shells, and in weak acids or muriate of barytes to 
obtain silicious shells. Various members took specimens for 
examination. 
