ox ARTESIAN AND FISSURE WELLS IN NEW BRUNSWICK. 145 



a less degree the sandstones of the Lower Carboniferous series in which 

 the wells of the third group are bored, are capable of transmitting 

 water; their grains are frequently held together by a cement of calcite, 

 which to some extent closes the openings between the grains. 



As the second class of wells have largely been made in rock that is 

 practically non-porous, the supply of water which such wells yield 

 must come from joint or fissures in the rocks, and for good practical 

 results it is obviously desirable that the positions in which such fissures 

 are likely to be numerous should be known, and also whether there 

 are chances that such fissures will be open, or fast closed by pressure. 



Proofs that there is a pressure in a horizontal direction approxi- 

 mately from the southeast, have been observed at Monson, Mass., by 

 W. H. Niles,* at New York by Prof. J. F. Kemp,t and at St. John, 

 N. B., by one of the writers. I Such pressure would have a tendency to 

 close fissures that were at right angles to it, especially where they 

 occur in yielding rocks like slates and soft schist, but would not inter- 

 fere with those that are horizontal, or run in the direction of the 

 the pressure. Hence joints with a low hade to the southwest, or joints 

 with a northwest course are in this region more likely to carry water, 

 than others. 



Dr. W. 0. Crosby, of Boston, has marshalled evidence to show 

 that joints do not extend to very great depths,^ and are most numer- 

 ous in the rocks toward the surface of the earth, hence in going 

 down on these fissures one may expect to find a level where the 

 water is held by the cessation of the fault or joint. Under these con- 

 ditions where these joints or fissures are numerous, they act as 

 reservoirs to hold fresh water that has been transmitted through them 

 from the surface of the earth, to the lower levels. 



Nordenskjold || from observations made on the coast of Finland 

 and Norway, has drawn the conclusion that at a certain depth in 

 metamorphic and crystalline rocks, horizontal fissures have been 

 formed by expansion and contraction of the rocks, due to the difference 

 in temperature of the rocks down to a certain depth in the summer, as 

 contrasted with the winter. The rocks down to the point where they 

 have a uniform temperature at all seasons, would contract in winter 

 and expand in summer. The theory requires that at this level of 



American Journal of Science, March, 1872. t Trans. N. Y. Acad., August, 1895, p., 275. 

 X Bulletin of this Society, No. XII, pp, 39, 1894. 

 SGeol, Mag., London, Sept. 1881, p. 316. 

 | Journal Royal Geographical Society, Vol. X, No, 5, pp. 465-469, Nov, 1897. 



