712 
Proceedings of the Royal Society 
was employed. He also introduced to the Society a phonograph 
made by Messrs Macgillivray and Scohie of Glasgow, which, for 
loudness, was superior to any one he had yet heard. 
3. Note on a Variation of the Microphone. By 
R. M. Morrison, D.Sc. 
Following out a suggestion made by Mr Seabrook in Nature of 
May 30th, I mounted the three carbon blocks of Professor Hughes’ 
microphone on, not as Mr Seabrook recommends, a plate of 3 inches 
diameter, but on a ferrotype plate about 6 inches by 4. This plate 
formed part of the top of a box, thus — 
Plate 
This form I found to be extremely sensitive, as a piece of cotton 
wool \ inch in diameter falling through 1 inch made a loud sound 
in the telephone. When the plate was lightly brushed by a camel’s 
hair brush the sound produced in the telephone could be heard a 
yard away. A small clock placed on any part of the table on which 
the microphone stood could be heard distinctly ; also a tap on the 
table, or even walking on the floor, each step producing a clang in 
the telephone. On speaking into the open part of the box the 
words spoken were distinctly and loudly heard in the telephone, 
notwithstanding the difficulty of hearing words spoken by one’s self 
at the same time. 
4. On the Action of Heat on some Salts of Trimethyl-Sulphine. 
Part II. By Prof. Crum Brown and J. Adrian Blaikie, B.Sc. 
{Abstract.) 
In the former paper on this subject, the authors stated that 
when hyposulphite (thiosulphate) of trimethyl-sulphine is heated 
to about 135° C., it loses sulphide of methyl to the extent of 23*58 
per cent., the salt at the same time fusing to a clear colourless 
liquid. On cooling, this solidifies to a hard, very hygroscopic crys- 
talline mass. 
