366 KANSAS CITY REVIEW OF SCIENCE. 
ning arresters are for the purpose of carrying the electric charge, that the heaven& 
may send, to mother earth, preventing it from entering the cable, burning through 
the insulation and reaching the operating-room where the damage it could do in 
a second can scarcely be estimated. The cables are supported on No. 4 iron 
wire, so hung that there is no strain on the cable. At the operating-room, where 
the strain on the ofifice pole caused by the weight of the cables is something enor- 
mous, a very elaborate system of "guying" has been constructed, and the poles 
evenly held in place that in all probability they would retain their positions were 
they sawed in two. 
The outside work which will increase the capacity more than one hundred 
per cent and, it is predicted, improve the service so that "trouble" will be re- 
duced to the minimum, is but one of the elements in the improvements being 
made. The operating-room on the fourth floor of the Wales Building, Sixth and 
Delaware Streets, is just now receiving its finishing touches. No one except those 
engaged in the practical management of an exchange appreciates the difficulties 
to be overcome in handling the connections that subscribers may call for in a 
large exchange. The Electrical Review, of New York, says : 
" The people at large, uninformed of the difficulties of the undertaking, are 
surprised and disappointed that electricity, after giving them so wonderful an 
instrument as the telephone, hesitates to make the use of it conveniently univer- 
sal. It is difficult to persuade them that there is, physiologically speaking, ten 
times the amount of valuable inventive tissue already expended on telephonic 
apparatus that there is on the telephone itself. It is a misfortune of the telephone 
business that the difficulties in the way of prompt and reliable service are not 
properly appreciated." 
The above paragraph appears in an article accompany ng a full page illus- 
tration of the new switchboard of the Kansas City telephone exchange. It is 
known as the "multiple switchboard," and consists of two more switchboards, 
to each of which is connected all of the lines of the subscribers of the exchange, 
and is designed to enable many switchmen {or swiichladies, as young ladies are 
to be the operators in the city hereafter) to operate the same wires on the differ- 
ent boards without interference. A simple test is provided by which the operator 
can tell instantly, without questioning another operator, whe.ther the line desired 
is free or " busy." The spring-jack (the receptacle for the connecting plug) used 
with the board is a small and peculiar looking combination of phosphor-bronze 
spring, screws and burrs and insulating compounds. The spring and contact 
point, against which the spring nominally rests, are both insulated from the frame 
of the jack which is connected by an independent wire to all its duplicate frames. 
In the Kansas City office three switchboards are in place, giving a capacity of 
six hundred wires. Others are to be added. All the lines come to the first 
board from the cable, which is carried under the floor to the back of the switch- 
board, where it is separated and each wire numbered. They are then carried *to 
the same number on the switchboard, connecting to the spring of the jack, pass- 
ing through the spring and the contact point, without touching the frame of the 
