64 On the Municipal Electric Telegraph, 
Signal and Alarm Station of the System in Boston, numbering 
sixty in all. These were constructed by Mr. Farmer, on the 
principle of conducting to the earth all free electricity, or elec: — 
tricity above a certain degree of tension, and will be figured here- 
ter. So large a number of these, employed in connection with © 
the circuits of forty-nine miles of wire, above the buildings, can — 
not fail to exert an important influence in silently discharging 
accumulations of atmospheric electricity. A general protection 
against danger from this source may thus be incidentally afforded 
by the Municipal Telegraph. 
In a perfect system of Fire Alarms it is necessary that commU- — 
nication should be instantaneous, universal and definite. The 
Electric Telegraph, by its peculiar properties, affords the means of 
fulfilling all of these conditions. Its pulsations are transmitted 
an inappreciable time over the wires of the Municipal circuit. By © 
the multiplication of Stations in the course of the Signal wires, by — 
which all parts of the City are brought into communication will 
the Centre, and by the electro-mechanical connection of the vat 
ous alarm bells with the Centre, the means both of signalizing 
and public alarm, are made universal. By the use of electro 
magnetic machinery, by which District Signals may be struck of | 
tolled upon the alarm bells, at will, the System becomes definite. © 
In the communication of a definite alarm, the division of @ | 
City into Fire Districts becomes necessary. These will vary 
each City according to its size and other conditions. The nam | 
ber should be sufficient to localize a fire without unnecessary 
complication. The following are the District Divisions which — 
have been adopted in Boston: I, North,—II, West,—III, Centre, 
—IV, South Centre,—V, South End,—VI, South Boston,— 
VII, East Boston. 
by the depression of either of the keys K, K, K, or of one of any | 
number of keys similarly situated between the wires. It will b¢ | 
