OF ENGLAND. 



Waterpower upon salmon rivers used for manufactur- 

 ing purposes 



Adding to the above three corn mills for every other 

 kind of mill, excluding all mills in Lancaster, York, Derby 

 and Chester, and all mills between the Humber nnd the 

 Medway. over an area of 8,604 square miles as unproduc- 

 tive of salmon .. .. .. 



Estimated total amount of water power used upon 

 salmon rivers in England and Wales in horse power .. 



Horse 

 Power in 

 Water. 



3886 



11658 



15544 



The water power for milling and manufacturing 

 purposes appears to be 28,617 horse power, or seven 

 per cent, when compared with the steam power at 

 374,869 horse power, or 93 per cent, of the whole ; 

 and the total quantity of water power used upon 

 salmon rivers may be estimated at 15,544 horse 

 power. Many of the mills do not exceed six or ten 

 horse power each, on small streams. A few may be 

 taken at twenty horse power and upwards each ; if 

 we take them to average twenty horse power each, we 

 get 777 weirs, or at twelve horse power each we get 

 1,295 weirs. I will estimate the larger number, that 

 is, 1,295. Of these weirs one-half may be taken at 

 four feet in height and under, and these could easily 

 be made passable to salmon ; the remaining half, or 

 647 weirs, I will estimate at the maximum rate of 

 60 each, according to Mr. FfennelFs calculation ; 

 thus, 647 at 60 each would amount to 38,820, say 

 40,000 as the expense of making fish passes over all 

 the weirs upon salmon rivers, extending over an area 

 of 34,730 square miles, in England and Wales. 



It appears from the Fishery Commisioners' maps 

 of all the rivers in England and Wales, that there are 



Rivers with an area of 20 to 100 square miles 

 100 to 300 ,, 



300 to 600 



600 to 1000 ,, 



1000 to 5000 



Total 



154 



32 



15 



5 



12 



218 



