iments
Taylor's system.--With diagram.

Theory of the Action of the Carbon Microphone.--What is it?
--2 figures.

The Dembinski Telephone Transmitter.--3 figures.

New Gas Lighters.--Electric lighters.--3 engravings.

Distribution of Heat which is developed by Forging.

V. ARCHITECTURE, ART. ETC.--Villa at Dorking.--An engraving.

Arm Chair in the Louvre Collection.

VI. GEOLOGY.--The Deposition of Ores.--By J.S. NEWBERRY.--Mineral
Veins.--Bedded veins.--Theories of ore deposit.--Leaching
of igneous rocks.

VII. NATURAL HISTORY, ETC.--Habits of Burrowing Crayfishes
in the U.S.--Form and size of the burrows and mounds.--Obtaining
food.--Other species of crayfish.--3 figures.

Our Servants, the Microbes.--What is a microbe?--Multiplication.
--Formation of spores.--How they live.--Different groups
of bacteria.--Their services.

VIII. HORTICULTURE.--A New Stove Climber.--_(Ipomaea thomsoniana)_

Sprouting of Palm Seeds.

History of Wheat.

IX. MISCELLANEOUS.--Technical Education in America.--Branches
of study most prominent in schools of different States.

The Anaesthetics of Jugglers.--Fakirs of the Indies.--Processes
employed by them.--Anaesthetic plants.

Epitaphium Chymicum.--An epitaph written by Dr. GODFREY.

* * * * *

IMPROVED FILTER PRESSES.

Hitherto it has been found that of all the appliances and methods for
separating the liquid from the solid matters, whether it is in the case
of effluents from tanneries and other manufactories, or the ocherous and
muddy sludges taken from the settling tanks in mines, some of which
contain from 90 to 95 per cent. of water, the filter press is the best
and the most economical, and it is to this particular process that
Messrs. Johnson's exhibits at the Health Exhibition, London, chiefly
relate. Our engravings are from _The Engineer_. A filter press consists
of a number of narrow cells of cast iron, shown in Figs. 3 and 4, held
together in a suitable frame, the interior frames being provided with
drainage surfaces communicating with outlets at the bottom, and covered
with a filtering medium, which is generally cloth or paper. The interior
of the cells so built up are in direct communication with each other, or
with a common channel for the introduction of the matter to be filtered,
and as the