260 



In his report to the Promoters of the Thames and Severn 

 Canal, he gives elaborate estimates, which contain the following 

 item : 



To Tunneling from Sapperton to Hayley Wood. This 



is an uncertain piece of business in point of expense, 



upon account of the different strata of matter through 



which it must be made, yet that it is practicable at 



this day will not be doubted, though it is much 



longer, and to admit 12ft. boats, must be wider than 



any that has yet been done. This Tunnel I have 



supposed to commence where the ground becomes 



24ft. above the surface of the water, (which will be 



30ft. from the bottom), according to which the length 



will be 3850 yards as appears by the annexed profile. 



I have likewise annexed a section of the form and 



dimensions, that I judge, too, will be proper to make 



the Brickwork to admit boats of 12ft. wide, so that 



they may have a sufficient waterway at the different 



heights of the water in the summit level ; and as the 



ground is from 24ft. to 203ft. high, the deep part 



will be more expensive than the other, upon account 



of sinking shafts, and drawing up the earth, and 



letting down the materials, therefore, I will suppose 



one half of the length to cost £10, and the other £9, 



per yard, running at which rate, 3850 yards comes to 36575 



To 97680 cubic yards of extra cutting to the mouth of 



the Tunnel, at 6d. per yard ... ... ... 2442 



£39017 



also for and on behalf of their successors do hereby further covenant promise 

 and agi-ee to and Avith the said James "Watt and Matthew Boulton their 

 executors administrators and assigns that they the said Company of 

 Proprietors of the said Navigation and their successors shall and will 

 yearly and every year during the residue and remainder of the said term of 

 twenty-five years or such part thereof as the said engine shall continue to 

 be used or worked at or upon any part of the said Canal of Navigation 

 aforesaid or in any other place well and truly pay or cause to be paid 

 unto the said James Watt and Matthew Boulton their executors adminis- 

 trators or assigns by two equal half-yearly payments in every year the sum 

 of one hundred and tiventy pounds lawful money of Great Britain the first 

 of which payments to begin and be made at the end of six calendar months 

 rjext after the day on which the said engine shall begin to be used or worked 



