32 Drills (17 by 174) 2,958 2 Shovels 1,600 Pumps, etc 1,000 3 Hoisting engines on concrete, each working one-third time 500 2 Derricks 1,000 ----- Total 7,058 The average number of drillers per shift was about 25 at the two main working faces. There were also from 5 to 10 drills trimming and cleaning up for concrete, say an average of 7, making 32 in all. After November 1st, it actually required three boilers under steam all the time, and not less than seven compressors running at full capacity, to keep the air at proper pressure, the theoretical capacity of the compressors being 8,750 cu. ft. of free air per min., as against 7,000 to 7,400 cu. ft., the theoretical maximum requirement. Some of this deficiency was due to losses in transmission, part also was due to the fact that the actual was probably considerably below the theoretical capacity of the compressors. ACCIDENTS. Two accidents occurred to the powder magazines, the causes of which were never absolutely determined. The first occurred on January 10th, 1907, when the dynamite burned up without exploding. The second accident was on March 3d, 1907, when an explosion occurred which damaged property over a very large area, but did not involve any serious injury to persons, only one man being slightly hurt. The only serious blasting accident in the tunnels occurred on January 26th, 1908, and was due to a premature blast, the cause for which could not be ascertained. _Contractor’s Organization._--The work was in general charge of a superintendent, and, during the time it was being carried on at both ends, an assistant superintendent had charge at night. At each end there was a day and a night walking boss, who had general supervision of the men in the tunnels, the day walking boss being the superior, and responsible for the general conduct of the work at his end, both day and night. Two 10-hour shifts were worked, thirteen shifts every two weeks, no work being done on alternate Sundays and Sunday nights. With the exception of the walking bosses and the master mechanic, all the men changed from the day to the night shift every two weeks. The organization was approximately as follows, for each shift: _General_--_Both Tunnels._ 1 Master mechanic (days only), 1 Machinist, 1 Engine runner, 2 Firemen, 2 Oilers, 1 Electrician and helper, 1 Drill machinist and helper, 3 Blacksmiths and helpers, 1 Powderman, 1 Walking boss, 4 Locomotive engine runners, 4 Brakemen, 1 Switchman, 1 Foreman on dump, 6 Men on dump, 1 Foreman on track, 6 Men on track. _In Each Tunnel._ _Drilling and Blasting._ 1 Foreman, 12 Drillers, 12 Helpers, 1 Nipper, 1 Pipe-fitter. _Mucking._ 1 Shovel engineer, 1 Cranesman, 1 Muck boss, 12 Muckers. RECORDS.