Today's photo is of the Rosslyn, a bucket dredger built by Lobnitz and Co. of Renfrew in 1912.

A bucket dredger is equipped with a bucket dredge, which is a device that picks up sediment by mechanical means, often with many circulating buckets attached to a wheel or chain. Very detailed information on bucket dredgers, how they work, their history and plans is available here.

Specification details are available from Clydebuilt database.