These guides must know the exact spot where they will meet the relieving troops and the best and safest way to the trenches. =25. SMOKING AND TALKING.=--After leaving the rendezvous there is to be no smoking or talking till arrival in the trenches. =26. RATE OF MARCH TO TRENCHES.=--The rate of marching to the trenches from billets will not exceed 2 miles an hour. =27. PROCEDURE ON ARRIVAL IN TRENCHES.=--(_a_) The troops being relieved will not leave the trenches until all trench stores have been handed over and receipts received, all the relieving troops are in position, and new sentries have been posted and orders to move have been received from the company commander. (_b_) Platoon commanders will at once personally examine all firing positions and satisfy themselves that each man can fire on the foot of the nearest part of the wire entanglement. (_c_) They will examine the ammunition and bomb magazines, vermorel and other sprayers, and antigas solution vessels. (_d_) When the relief is completed O. C. companies will report to that effect to battalion headquarters. (_e_) Men will not be dismissed till the O. C. company has received reports from all his platoon commanders that everything is in order. =28. ENGINEERS.=--(_a_) To insure continuity of work a few sappers should live permanently in the trenches. (_b_) Daily requisitions for engineering material required will be forwarded by company commanders to battalion headquarters. (_c_) The battalion commander will apply to the field company for the material required through the brigade headquarters and will arrange for carrying parties to take it in. =29. PREVENTION OF CHILLED FEET AND FROSTBITE.=--(_a_) Before marching to trenches, feet and legs will be washed and rubbed with antifrostbite grease or whale oil under platoon supervision. Boots should be large enough for two pairs of socks, and puttees must be put on loosely. (_b_) The march to the trenches will be in ankle boots, every man will carry two pairs of spare socks, spare grease, and towel. (_c_) On arrival at the trenches, take off ankle boots and wet socks, dry and grease feet, put on dry socks, gum boots (trench stores) or paper stockings and ankle boots. (_d_) During the tour in the trenches, circulation must be kept up by movement; the restriction of the circulation of the lower limbs is the principal cause of chilled feet. (_e_) Boots and puttees will be removed at least once in every 24 hours, feet and legs will be dried, rubbed, and greased, and dry socks put on. (_f_) Gum boots will be taken off before troops march out on relief and will be handed over as trench stores to the relieving unit. (_g_) On arrival in billets, feet will be washed and rubbed; dry socks, hot drinks, and food will be provided under battalion arrangements.