102 Mr. W.J. Henwood's Notes on some recent Improvements 



Millions. 

 1828: average of all the pumping engines reported 37'2 



Huel Towan, Wilson's engine... 77'2 



Consolid. Mines, Woolf's engine 62*5 



Huel Vor, Trelawny's engine 55' 



I think the foregoing details prove, not only that Captain 

 Grose led the van of the more recent improvements, but that 

 he has kept far in advance of its strides. The importance of 

 the saving thus obtained cannot be more plainly shown than 

 by the following extract from Mr. Taylor's valuable " Re- 

 cords" J. " In 1825, all the drainage of the Consolidated Mines 

 was effected by three engines only ; they were hard pressed 

 b}' the increased depth of the mine and quantity of water, and 

 derangement happened, which, added to the bad state of some 

 boilers, and the pit-work, which suffered from the engines 

 being unavoidably worked too fast, the duty of the engines 

 fell off considerably, and, as the reports will show, did not 

 average quite 30 millions ; at that time the monthly consump- 

 tion was 



Job's engine (90-inch cylinder) 4992 bushels. 



Pearce's do. (58 do. ) 3615 



Bawden'sdo. (90 do. ) 8427 



1 7034 

 " At the present time (1829) six engines are at work, as, 

 to remedy the evils above stated, and to provide for sinking 



» For all 1828, it took the lead of the Consols', engines. 



f In this month an experiment was made by Cornish engineers, duty 

 872 millions; and in April 1830 by Mr. Rennie and myself, duty 

 92,260.202 by calculation, and by tualct- delivered as determined by a float 

 83,602,022. 



% Records of Mining, p. 164. 



deeper 



