As early as January, 1851, while the building was still under the control of the contractors, a party of four men of the royal sappers and miners patrolled the building and its workshops every evening after work, remaining until they had seen every fire and light properly extinguished except those in the offices, where the great press of work rendered it necessary to allow fires and lights to be kept up during the night. With the addition of a party of the London fire brigade, this arrangement remained in force until the opening of the building, when a picquet of twenty-four men of the corps was mounted in the building at eight P.M.; this party on arriving at the Exhibition was marched round it to all the stations where the different fire-engines, fire-cocks, tanks, buckets, &c., were placed; thus every individual ascertained that all the stores were correct and ready for use. The whole of the men of the corps at the Exhibition had been drilled to the fire-engines, and made acquainted with all the arrangements undertaken to provide for the immediate extinction of any fire. The twenty-four men slept in the building every night, one man remained on sentry to be in readiness to rouse the men in case of alarm, and a non-commissioned officer and two men patrolled the building every two hours. The picquet came off duty at six A.M., when another party of the sappers relieved them for the usual daily duty. This arrangement continued until the 4th November, 1851. The number was then reduced to twelve, and on the 11th November to two men, who remained all night in the building until it was again given over to the control of the contractors, Messrs. Fox and Henderson, in December, 1851.