40 Report of the American 



ON THE PENNSYLVANIA FISH-WAYS. 



BY JAMES WOERALL. 



During the early spring and summer of 1874, we carefully observed 

 the working of our structure. We have no doubt at all but that large 

 numbers of shad passed through it during high water in the Susquehanna. 

 At least three thousand shad were caught above the Columbia dam in the 

 Susquehanna river during that season. This being of course but a small 

 percentage of the number of fish which actually crossed over the dam. 



During the fall of 1874 large quantities of the small shad, which were 

 the hatching of the spawn deposited above the dam b}' the fish which made 

 the transit during the last summer, were constantly seen making their 

 way down the stream to the sea. We are consequently led to believe 

 that we have attained a measure of success in the erection of our fish-waj- 

 as a transit for shad in advance of any that has ever been reached in the 

 history of fisheries in this country or the old world. We are firmly 

 convinced that our fish-way, as it stood in 1874, was operative in a high 

 stage of water ; we are just as firmly convinced that during a low stage 

 of water our fish-way was inoperative and ineflficient. During the fall of 

 the past 3'ear we attempted the alteration of the fish-ways so as, if posi- 

 ble, to make it available for the purpose of allowing a free transit of 

 shad at all seasons and at all stages of the water. To accomplish this 

 we had the floor of the fish-way torn up for the distance of 100 feet and 

 lowered, so as to carry the toe of the fish-way considerabl}' below the 

 surface of the water. 



The run of shad in the season of 1874 commenced on the 11th day 

 of May, and fishing, to any considerable extent at Havre de Grace, the 

 mouth of the river, ceased on the 20th. Thus making the run of fish 

 but a little more then a week from which the entire upper river was to 

 have been supplied. Rain did not occur in this region until late in 

 June or until the beginning of July. So drouth may be said to have 

 set in at that early day, even during the fishing season. The river at 

 once commenced falling, and the result was that the reaction natural to 

 low water occurred whilst still the fish were running. The stage 

 that low water reached was lower than that seen in many 3'cars. This 

 state of the water left the toe of our fish-way on a level with the water in 

 the pool below the dam. The water descending the fish-waj', acquired 

 suflScient velocity to make a deep hollow in the water of the pool below, 

 and to create a large reactionary wave. This reaction undoubtedly 



