rifles.  Crew of 3 men per rifle.  Usually posted to
          enfilade the entanglements of the first line.  They
          concentrate the fire effect of from 7 to 10 riflemen. 
          Effective range:  up to 300 yards.
      (c) Rifle Grenadiers.  Located near enough to first line to hold
          the enemy trenches under fire and deliver effective barrages
          near the mouths of our own communicating trenches.  Should be
          located near observation posts so that their fire can be
          promptly corrected.
      (d) Trench mortars.  Located similarly to (c).  Manned by
          riflemen.
      (e) Bombers.  One supply man to each 2 grenadiers.  Used for
          protection of auto-rifles, in counter attacks, for
          protection of communicating trenches and fighting in close
          quarters.
      (f) Riflemen.  Posted to deliver frontal fire.  Grouped according
          to the plan of counter attacks.
      (g) As many men as possible should be instructed in the use of
          the enemy’s weapons.

   D. LIAISON: 

      (a) By telephone.  Quickest and most accurate.  Maintained
          between each platoon and its company headquarters, and
          between adjoining companies.  Especially subject to
          destruction in bombardment.  Wireless and ground telegraphy
          are used only between brigade and division headquarters.
      (b) By runners ("liaison agents").  Five detailed from each
          company to battalion headquarters; one sent to each
          adjoining company headquarters; one from each platoon to
          company headquarters; four or five on duty at each platoon
          headquarters; five from each machine gun company to
          battalion headquarters.  Messages sent by them should, if
          practicable, be written and signed, and should be receipted
          for by the addressee.
      (c) By rockets and flares.  Quickest means of liaison with the
          artillery in rear.
      (d) Domestic (message carrying) grenades.
      (e) Dogs and carrier pigeons.  Sent out to the rear from
          battalion headquarters.
      (f) One searchlight—­with a radius of 3 miles—­is furnished to
          each company.
      (g) Noise.  Klaxon signals, etc., give warning of gas attacks.

E. OBSERVATION: 

(a) Observers: 
1.  Must be men of infinite patience, keen hearing and
eyesight.
2.  They are located behind the first line in positions
combining good view with concealment.
3.  Each is provided with a panoramic map, made from
aeroplane photographs, of the enemy’s trenches.  On this
must be promptly noted every slightest change in the
trace, height of parapet, etc., of the enemy’s line.  Such
notes greatly assist in locating machine