Between the beginning of October 1866, when records begin and the end of 1874 when he sold his business, Thomas Messenger was involved in excess of 700 estimates or orders for heating systems. 1868 appears to have been the most successful year with in excess of 120.

Predictably horticultural heating systems underpinned all of Thomas Messenger’s other heating system applications. Whilst they were no doubt seen as significant in their own right, they were far less important in terms of both volume and especially revenue. Between the end 1866 and the end of 1874 horticultural heating systems probably accounted for over 80 per cent in volume terms of all heating systems.