Chapter IV: ELECTRICITY, LIGHT, ETC.--Early History of the Telegraph

--Pyrsia, or the system of telegraphy among the Greeks.
--Communication by means of characters and the telescope.
--Introduction of the magnetic telegraph between Baltimore
and Washington

The Kravogl Electro Motor and its Conversion Into a Dynamo
Electric Machine.--5 figures

Bornhardt's Electric Machine for Blasting in Mines.
--15 figures

Pritchett's Electric Fire Alarm.--1 figure

A Standard Thermopile

Telephonic Transmission without Receivers.--Some of the
apparatus exhibited at the annual meeting of the French
Society of Physics.--Telephonic transmission through a
chain of persons

Diffraction Phenomena during Total Solar Eclipses.--By G.D.
Hiscox