HOWIETOUN PONDS. 261 



The feeding of the fry in the 20-feets still required much 

 attention. In all the ponds the fry scattered, as only fry can ; and 

 it took an hour of patient coaxing to collect them for feeding, 

 during which much food fell to the bottom, and lay unconsumed, 

 necessitating the ponds being frequently brushed out. The feeding- 

 jars were tried, but the area of each pond was too large for them 

 to cope with ; and the old man who helped me to feed did not see 

 so well as once, and did not then (he has improved since) make a 

 successful nurse. So at last I made a water-wheel, and placed it 

 in the trough carrying the main supply to the ponds ; on the axle 

 a small grooved wheel is placed, and copper pins driven into the 

 groove at suitable distances. Over the trough feeding the 20-feets, 

 a driving-shaft was fixed, carrying two eccentrics, and at the end a 



FIG. 184 scale 



studded wheel driven by a chain passing over the small grooved 

 wheel on the axle of the water-wheel (Fig. 184). Spoons made of 

 perforated zinc, and attached to short but flexible handles, bored 

 near the end to receive a pin, were constructed, and steel pins 

 fixed in the sides of the 20-feets, about 5 feet from the upper 

 ends ; 9 inches further iron rods 6 inches in length were pivoted. 

 Below are diagrams showing details (Fig. 185). 



The modus operandi is as follows : Collars of copper wire are 

 fitted, one on each eccentric. From these collars strings lead to the 

 four rods, one on each 20-feet pond. These strings are adjusted 

 so as to have 4 to 6 inches of slack. A lead weight depends from 

 each string, and is placed so as to travel freely between the rod and 

 the handle of the spoon round which two or three turns of the string 

 are next wound. Balls of finely-chopped meat are made, each ball 

 the size of a large walnut, and two or three balls are dropped into 

 each spoon. The chain is then passed over the driving-wheels, 



