total costs being $4,120,000 and $7,980,000. These figures are for condition No. 1, in which all piers and anchorages were assumed to be sunk by the pneumatic process to bed rock.

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For condition No. 2, in which there is no bed rock within reach of the piles, the corresponding figures were $4,420,000 and $7,030,000.

The suspension-bridge anchorages resting on piles were found to be so much cheaper than those resting on bed rock that it was concluded to adopt them for condition No. 1, and to assume the piles to be driven to bed rock.