Now, if you put your ear to the receiver of a field-telephone, you find yourself, as it were, suddenly thrust into a vast subterranean cavern, filled with the wailings of the lost, the babblings of the feeble-minded, and the profanity of the exasperated.  If you ask a high-caste Buzzer—­say, an R.E.  Signalling Officer—­why this should be so, he will look intensely wise and recite some solemn gibberish about earthed wires and induced currents.

The noises are of two kinds, and one supplements the other.  The human voice supplies the libretto, while the accompaniment is provided by a syncopated and tympanum-piercing ping-ping, suggestive of a giant mosquito singing to its young.

The instrument with which we are contending is capable (in theory) of transmitting a message either telephonically or telegraphically.  In practice, this means that the signaller, having wasted ten sulphurous minutes in a useless attempt to convey information through the medium of the human voice, next proceeds, upon the urgent advice of the gentleman at the other end, and to the confusion of all other inhabitants of the cavern, to “buzz” it, employing the dots and dashes of the Morse code for the purpose.

It is believed that the wily Boche, by means of ingenious and delicate instruments, is able to “tap” a certain number of our trench telephone messages.  If he does, his daily Intelligence Report must contain some surprising items of information.  At the moment when we attach our invisible apparatus to Mr. M’Gurk’s wire, the Divisional Telephone system appears to be fairly evenly divided between—­

(1) A Regimental Headquarters endeavouring to ring up its Brigade.

(2) A glee-party of Harmonious Blacksmiths, indulging in the Anvil Chorus.

(3) A choleric Adjutant on the track of a peccant Company Commander.

(4) Two Company Signallers, engaged in a friendly chat from different ends of the trench line.

(5) An Artillery F.O.O., endeavouring to convey pressing and momentous information to his Battery, two miles in rear.

(6) The Giant Mosquito aforesaid.

The consolidated result is something like this:—­

REGIMENTAL HEADQUARTERS (affably).  Hallo, Brigade!  Hallo, Brigade! 
HALLO, BRIGADE!

THE MOSQUITO.  Ping!

THE ADJUTANT (from somewhere in the Support Line, fiercely).  Give me
B Company!

THE FORWARD OBSERVING OFFICER (from his eyrie).  Is that C Battery? 
There’s an enemy working-party—­

FIRST CHATTY SIGNALLER (from B Company’s Station).  Is that yoursel’,
Jock?  How’s a’ wi’ you?

SECOND CHATTY SIGNALLER (from D Company’s Station).  I’m daen fine! 
How’s your—­

REGIMENTAL HEADQUARTERS.  HALLO, BRIGADE!

THE ADJUTANT.  Is that B Company?

A MYSTERIOUS AND DISTANT VOICE (politely.) No, sir; this is Akk and
Esses Aitch.