stated that he was in want of some photographic illostrations 
of quarries and other points of geological interest for the 
[forthcoming publication of the society, and he requested 
the assistance of the members of the section in taking 
negatives of localities to be pointed out, and in printing 
positives. Two members at once promised assistance. Mr. 
Alfred Noble read a paper on the " The Chemistry of the 
Sewage Question." After glancing at the importance of the 
subject, and naming the valuable constituents of sewage, the 
author stated that it might be regarded either in the purely 
sanitary, or in the utilitarian point of view. He then spoke 
of the system of water carriage, now so extensively adopted, 
and the plans at present in use for employing sewage, by 
irrigation, upon land, expressing his opinion that too much 
faith was put in that mode of working, and concluded by 
strongly advocating the use of dry earth as the best means 
both of disinfecting and removing in a small compass the 
valuable product in such a form that it could be at once ap- 
plied t© the land without inconvenience, a plan which had 
been developed by the Rev. Mr. Moule, of Dorchester. 
After some discussion, especially on the practical working of 
Ibis new plan, which appeared satisfactory, Mr. John Beattie 
made a communication on the Wohlthytype, so much talked 
of liitely, as producing photographic pictures that did not 
fade. He said he had seen pictures in London which were 
vigorous, delicate, and soft ; but that the specifications of 
the process were very incomplete, and his relations with the 
company unsatisfactory, so that he had not Leen very suc- 
cessful in obtaining good prints. The uranium salt em- 
ployed acted solely as a reducing agent, like gallic acid, and 
the picture was in the paper, aud not on the surface, the 
collodion film acting as a glaze, so that he considered them 
quite as likely to fade ?,nd from the same cause as ordinary 
photographs, 
Botanical Section, Dec. 17th. — Mr. Leipner in the 
chair. This evening was devoted almost entirely to practical 
j instructions by the president in the use of the microscope, 
and in the preparation of specimens for future observation, 
for the benefit of those members who wished to be able to 
make use of the microscope in Botanical research. The 
method known as dry mounting was fully explained and 
illustrated, the question of mounting in fluid being reserved 
for a future occasion. In most cases it was desirable to 
surround the object with a cell, or ring, which might be 
made of cement, cardboard, zinc foil, vulcanite, and then 
fastened to the glass slide by ordinary liquid or marine glue. 
In dry mounting, the object was simply placed within this 
cell, snd covered with thin glass. Frequently, however, the 
cell was filled up with Canada balsam, in which case it was 
desirable to soak the object first in turpentine or chloroform, 
and then to apply a slight degree of heat to cause the balsam 
to flow freely over the little inequalities of surface. Some 
large forms of Diatoms from Germany were shown, and Mr, 
Leipner exhibited some dried fronds of Nifodium molle, 
Woodwardia radicans, Pteris tricolour, and other ferns, as 
well as some fine specimens of Funaria hygro metrica, and 
other mosses in fructification. 
F. ASHMEAD, 
J. BARBER, 
A. NOBLE, 
T, H. YABBICOM, 
WM. LANT CARPENTER, 
Honorary Reporting Seoretary. 
