The organisation of the Battalion in 1914

The 5th Battalion of the Gordon Highlanders was a Territorial unit, recruiting in the Aberdeenshire and Banff areas of north east Scotland. The Territorials replaced the Volunteer Force in April 1908.
The organisation of the 5th Battalion was as follows:
Headquarters: Peterhead.
A Company: Strichen with drill stations at New Pitsligo, New Aberdour, New Deer and Maud.
B Company: Peterhead with drill stations at Longside and St Fergus.
C Company: Peterhead with drill stations at Boddam and Hatton.
D Company: Turriff with drill stations at Fyvie and Cuminestown.
E Company: Ellon with drill stations at Auchnagatt, Methlick, Skilmafilly and Newburgh.
F Company: Old Meldrum with drill stations at Tarves, Newmachar and Pitmedden.
G Company: Fraserburgh with a drill station at Rosehearty.
H Company: Fraserburgh with a drill station at Lonmay.

At the outbreak of war, the battalion was organised into eight companies of approximately 100 men each.  However, since 1913, Regular battalions had adopted a four company arrangement, each of about 240 men, an organisation imposed upon Territorial units by early 1915.
The Territorial Force had been established by the Haldane Reforms in 1908, and replaced the earlier Volunteer and Yeomanry forces.  Men from the age of 17 enlisted for a period of four years, which was automatically extended by one year in time of war.  Their training consisted of one or two sessions of drill a week, an occasional weekend camp, and an annual fifteen day camp, usually held between May and September every year. 

The primary roll of the Territorials was Home Defence with no requirement to serve overseas.  However members could undertake voluntarily to commit to this Imperial Service obligation.  By September 1913 only seven per cent of officers and men had chosen to do so.
Under the 1908 reorganisations, the following arrangements were put in place for the mobilisation of the Army:
On the outbreak of war
The troops with the colours [i.e. the members of the Regular Army], were mobilised
The Regular and Specialist Reservists were called out
The Territorial Force was embodied
 A 1909 manual estimated that:
The wastage of the regular army in its expeditionary character is calculated at a rate of not less than 80 per cent per annum. The First and Second Battalions may maintain themselves for a short period.  Their deficiencies will then normally be met by drafts from the Special Reserve, supplied in the earlier stages out of the existing material, and in the later by the ordinary operation of recruiting."
The manual then describes the function of the Territorial Force:
On embodiment, [the Territorial Force will] proceed to undergo a continuous course of six months' training on a regular basis, being either billeted or encamped, according to circumstances.  Their previous training has been elementary and elastic, but on embodiment it is thorough and exhaustive.  Their mobilization is therfore a mobilization, not immediately for war, but for a war training. . . As however the Territorial Force hardens and is perfected by training, the home portion of the regular army is to a corresponding degree released from the task of home defence, and becomes available in its entirity as a force for overseas, whether to attack a foreign enemy or to preserve peace within the borders of the Empire.
Baker, Harold. The Territorial Force : a manual of its law, organization and administration, with an introduction by R.B. Haldane.  London : John Murray, 1909