the British military
authorities at home and abroad. An old type of prisoner-of-war mark
dated 1800 is illustrated in _Fig._ 41, from "Pre-Victorian Postage
Stamps and Franks" by Mr. G. A. Foster.[4]

[Footnote 4: London. 1910: Charles Nissen & Co.]

[Illustration: 41]

The following are examples of the marks now being used (_Figs._ 42,
43):

[Illustration: 42 43 42A. 43A.]

It may be well to give a brief outline of the methods of the Army
Postal Service, that its work may be better known and understood.
In addressing letters to the troops it is important to give the full
military particulars of the addressee, _viz_:--Regimental number,
rank, name, squadron, battery or company, battalion, regiment (or
other unit), staff appointment or department, and title of the
Expeditionary Force. With these details set out clearly on the
envelope, the work of the Army Postal Service is facilitated and the
letter stands every chance of going through without delay.

In France, as the postmarks already illustrated denote, the British
Army Postal Service has several grades of post offices. The chief is
the Base Post Office, the principal sorting establishment for all mail
matter passing between our British Post Office and the Army Postal
Service. The Base Office is quite a large concern and has a vast
amount of clerical work to perform. In it letters are sorted,
letters taking precedence over all other mail matter, after which the
newspapers, and lastly the parcels are dealt with. Accounts of all the
branch post offices are filed and the general routines and formulae of
the Post Office at home are adhered to in detail. Letters, etc., for
services, departments and units at the base are put into callers'
boxes for delivery to the post orderlies. Those for more distant
services and units are forwarded to the various grades of branch
offices.

At the Base Office one of the most complicated and difficult tasks
is the re-direction of letters. Here are kept hospital lists, giving
names of men away from their units in hospital, and these hospital
rolls are revised weekly. Here also records have to be kept of the
movements of the units, and these records are constantly in process of
revision, and frequent communication is maintained with every branch
office in the field.

From the Base Office mails for field units are forwarded to the
Advanced Base Post Office, which in its turn distributes them to
the Field Post Offices serving the