president's address. 171 



"The strangest thing to my mind is that the cylinder 

 requires to be regularly scaled like a boiler from the scale 

 deposited by the injection water ; it seems funny to think of such 

 a thing." 



As late as 1899 a Newcomen engine continued to work at 

 Coalbrookdale. Another at the works of the Asliton Vale Iron 

 Company at Bristol, l)elieved to have been erected about 1750 or 

 1760, remained at work till it was pulled down in 1895, but no 

 doubt certain renovations were made from time to time. But it 

 had been worked by an old man since he was a boy, and by his 

 father and })y his grandfather before him. 



Another erected at Caprington Colliery in 1806 is believed to 

 have been originally built between 1770 and 1780 and worked 

 without separate condenser up to July, 1901. 



Numerous others are referred to by various correspondents, 

 but these examples are sufficient to show the persistent vitality of 

 the original Newcomen engine. 



Mr. Davey, with the assistance of ]\Ir. Richard B. Prosser, 

 gives the following chronological table : — 



1698. Thomas Savery of London obtained a jmtent for raising 

 water by the elasticity of steam ; Savery' s engine had 

 no piston. 



1702, Savery's "Miners' Friend" published. Savery' s advertise- 

 ment in Post Man, March 1 9th to 21st, notifying that 

 this engine may be seen at work " at his workhouse in 

 Salisbury Court, London." This advertisement was 

 printed in Notes & Queries, 27 January, 1900. (9 Ser. 

 vol. Ixiv). 



1712. Newcomen erected an engine near Dudley Castle for a 

 Mr. Back of Wolverhampton. This engine had a water 

 jacket around the cylinder condensing the steam, but 

 afterwards injection in the cylinder was adopted. All 

 valves worked by hand. 



1712 to 1718. A buoy used to give automatic action to the 



injection cock. 

 1711. A Newcomen engine said to have been eretted at Wheal 



Vor in Cornwall, and another at Ludgrove in 1720. 



