54 A STATISTICAL ACCOUNT OF THE 



the place of practical talents. The expedient of form- 

 ing an artificial embankment of stone and sand, promis- 

 cuously thrown around the footing of the piles, was 

 attended with compleat success. It saved the eastern, 

 and was essential to the security of the western dam. 

 Many hundred perches of stone were used ; and great 

 quantities of sand ; which, having been washed in by the 

 stream, consolidated the mass which now forms a perpe- 

 tual protection to the foundations. Both these dams 

 were exposed to ruin ; by the cross ties connecting the 

 inner and outer walls, or ranges of piles. The space 

 between them Avas filled, or puddled, chiefly with loam, 

 found to be the best filling. The ties were horizontal, 

 and of large timber; permitting, under each of them, a 

 sinking or settlement of the puddle; which afforded 

 cliannels, or courses, for constant streams of heavy leak- 

 ages ; which were, with great difficulty, kept under by 

 many pumps. These pumps were worked by horses, 

 and labour of men. Thev were inareniously contrived ; 

 one of them (far superior to the best chain pump) was 

 made by George Clymer of Philadelphia, a self taught 

 mechanic; capable of throwing out 400 gallons per mi- 

 nute, and not subject to choak with sand, or even small 

 pebbles, chips or filth. This pump voided nearly half 

 the water evacuated from the dam. Twelve hundred 

 gallons per minute have been (when hard pressed) 

 ejected by all the pumps ; commonly 600 to 800 gallons, 

 when the head, encreased by the tide, augmented the 

 leakages. The mischiefs attendant on the ties, were 

 the only faults experienced in Mr. JFestoji''s, otherwise 

 perfect, and really admirable, plan of the western dam. 

 The eastern dam was quadrangular; the western, hex- 



