82 BULLETIN OF THE NATURAL HISTORY SOCIETY, 



bed of the stream is the mean water level at the mouth.* But 



even without this the evidence is complete ; for I have obtained 



specimens of water from both surface and bottom at Fredericton 



and Indiantown at high water and their specific gravities reduced 



to 0° C. I find to be 



T, 1 . ^ { Surfa<3e water, .... 1.0005 | 

 Fredericton, -J ^^^^^^ ^^^^ ^^^^^ ^ ^^^3 ^ 



-r T J. ( Surface water, .... 1.0054 | 



Indiantown, <[ ^^^^^^ ^^^^ ^^^^ ^^^^^ ^ 



Thus to within one-fiftieth of one per cent the water at 

 Fredericton has the same density at surface and bottom. Even 

 at Indiantown the process of mixing of salt water and fresh 

 water is well advanced, for the density of the surface water is 

 raised to 1.0054, and that of the bottom is lowered from 

 al)out 1.026 which is the average density of sea water to 

 1.0109. When the diffusion has proceeded thus far even at 

 Indiantown, it is evident that the tide will not have progressed 

 many miles up river before the mixing is practically complete. 

 How far salt water actually does travel up stream cannot be 

 stated. It has been known as far as Gagetown. 



As regards the amount of tidal current, I may note that on 

 the morning of Monday, August 4th, I saw at Oromocto a log 

 float one and a quarter miles up stream in the main channel in 

 two and a half hours. That was at high water of a spring tide. 

 That it was an unusual amount of up-current was evident from 

 the extent to which it seemed to puzzle a ferryman. Also at 

 Fredericton on Aug. 22nd, at 4 p. m., I observed a feeble current 

 up. A careful examination of this whole (juestion would be of 

 great importance in such discussions as to whether the discharge 

 of sewage into the river below Fredericton could affect the 

 waterworks above the city. 



In conclusion I wish to express my indebtedness to Mr 

 S.W. Kain and Mr. Percy Cr. Hall, of the Natural History Society? 

 also to JNIr. Thomas Loggie, of Fredericton, Pi'ofessor Davidson, 

 of Fredericton, and Mr. E. T. P. Shewen, of St. John, l)esi(Ies 

 the gentlemen previously mentioned, all of whom have been so 

 kind as to supply me information or assistance. 



* S**« Youner's General Astronomy, p. 477. Airy's Article, Tides and Waves — 

 Eney. Metropolitana. 



