8 ROY A L SOriKTY OF (A NA I lA 



from its hidden recesses. Tin's is collected in quantity from lakes, and 

 reservoirs on the high levels, and carried lor miles by ditches, aqueducts 

 and flumes, to the banks of a primeval, deserted river channel, at tho 

 bottom of which, under forest covered clay banks, lies the auriferous 

 gravel studded with boulders and resting on the bed rock. Under a head 

 of about 300 feet " six inch rapid fire " hydraulic guns are pointed 

 against the bank, breaking down the earth, uprooting trees, scattering 

 boulders and washing out the gold — wdiich remains in the traps set for 

 it in the bottom of the sluices after all else has been carried off by the 

 power of the water. 



These "machine guns/' called "giants" and ''monitor?,"' are 

 models of simplicity as well as of ingenuity and efiSciency. While work- 

 ing they are great consumers of water, — and can only be used when 

 the ground is unfrozen, but this season is generally sufficient to use up 

 all the water which can be collected at the necessary elevation. 



It requires at least two men to hold and direct the force of the is- 

 suing stream from an Ottawa fire hydrant, but a boy can direct the 

 movement of a stream, twenty times greater in quantity and fifty per cent 

 stronger in pressure, as it rushes forth from the nozzle of one of these 

 " giants ", — which is fixed to a well secured platform, and moved for- 

 ward as the bank in front of it melts away, 



A thin short tube, of larger diameter, projects beyond the nozzle to 

 which it is fixed by gimbals, so that the tube can be moved independ- 

 ently, both horizontally and vertically, to touch the issuing stream, 

 w^hich immediately recoils from the obstruction, moving the '*' giant's " 

 nozzle in the opposite direction. Thus a boy " behind the gun " can 

 control its movement and compel the " giant " to fall back upon his 

 own resources for motive power. 



HORSE POWER, 



It is impossible to give anything but an approximate estimate either 

 of quantity or value of the available water po^ver over so vast an area, 

 because the first would involve the survey of every power site; and, as 

 to the second, the value begins when the power is wanted. 



All which now can be done is to state the conditions and endeavour 

 to estimate tho quantity, hypothetically. What is needed for an estimate 

 is the qiumtity of water and the amount of fall which can be relied upon 

 at the site for each power. To get the first, a measurement of the mini- 

 mum flow at each point w^ould be necessary in low water years, and for 

 the second, some local knowledge as to river levels, back water, etc. 



In the absence of such surveys we must fall back upon the average 

 rainfall of the whole region as far as that can be procured for any time, 



