This was a technique of improving the efficiency of a standard simple Boulton & Watt beam engine.
The Robertson Street workshop was operated by William McNaught & Son as "Makers of Steam-Engine Indicators, Steam Gauges, etc" at 12 Hampden Terrace, Glasgow, at least until 1895.
[3] MacNaught died in Chorlton upon Medlock, Manchester, on 8 January 1881, leaving two sons who carried on the business.
[1] A beam engine might run at 5 psi (34 kPa), using one low-pressure cylinder steamed by an 1840 wagon boiler,[4] but when McNaught'ed the new high-pressure cylinder could run at over 60 psi (410 kPa), which the then-new Lancashire boiler could produce.
The Cellars Clough mill engine was McNaught'ed by Woodhouse and Mitchell of Brighouse in 1909.