[5] In 1883, the company designed a new type of high speed steam engine which was used to generate electricity on board ships.

The vast majority of these vessels were assembled at the Jessie Street works using nuts and bolts, then dismantled and shipped as parts in crates to their client destination where they were re-assembled using rivets.

In 1945 it became a subsidiary of Glenfield & Kennedy Ltd.[1] Alley & McLellan continued to operate in the original Sentinel Works in Jessie Street, Glasgow until the 1950s, producing various engineering products.

The design offices and pattern shop is Category A listed as a building of significant national importance.

[15] In 1915, a subsidiary company, The Sentinel Waggon Works was created in Shrewsbury, England, to focus on the production of land-based powered vehicles.

The modern factory was pre-fabricated in Glasgow for rapid assembly giving the local management a state-of-the-art design and production facility.