Pits are provided under these tracks to enable the motors to be taken out or other repairs to be made. The floor and foundations of the station are of concrete. ... At Park street, the excavated earth was mainly a firm clayey gravel, but with a stratum one or two feet thick of very fine sand in the middle of its depth. Towards the ... A system of under-drains was laid to keep this water below the concrete masonry.
|Title||:||Annual Report of the Boston Transit Commission, for the Year Ending ...|
|Author||:||Boston Transit Commission|