218 EEPOKT OF COMMISSIONER OF FISH AND FISHERIES. [4] 



of 50 feet and connected together so as to enter a 4-incli main leading to 

 the water-tower. Water from the first pipe, at a depth of 48 feet and 

 flowing 20 gallons per minute by hand pump, contained 13.3 grains of 

 chlorine (corresponding to 21.9 grains of salt) to the imperial gallon ; 

 rather less than the proportion shown at first by the well E. As deliv- 

 ered from the well it ai)peared to be very good water, clear and soft, 

 and characterized only by a peculiar flat taste, as if insufiflciently 

 aerated. 



During these last drives (F) specimens of the soil from different 

 depths, as thrown up in the washings of the force pump, have been 

 preserved and set up in a glass tube, so as to show the layers met with. 

 From above downwards these are about as follows : 



At 9-foot contour : From surface to 7 feet, loose sand and gravel 

 (made land) ; from 7 to 9 feet, clay and fine sand (more sand than clay) ; 

 from 9 to 15 feet,* fine sand and gravel, growing coarser downward ; 

 from 15 to 10 feet, clay and fine sand (more clay than sand) ; from 10 

 to 23 feet, fine sand, growing coarser downward; from 23 to 50 feet,* 

 giavel, growing coarser downward. 



At the bottom of the borings the gravel is made up of coarse pebbles, 

 from the size of a pea to that of a hazel-nut. 



There are, then, in this region two water-bearing layers ; the first 

 below a bed of clay and fine sand, and in a loose sandy soil ; the second 

 below another, stifi'er, bed of clay and sand, and in very coarse gravel. 

 This last water-bed rose in the i)ipes to a level of 6 feet from the sur 

 face, or 3 feet above mean low water, and, as nearly as Ave could de(?ide, 

 to just about the level of the water in the natural spring above men- 

 tioned, upon Mr. Davis's land. The agent of the Boston Artesian Well 

 Company believes, and it seems to be probable, that this water supply 

 comes from the hills to the north and east, and does not extend far to 

 the westward of the wells. In confirmation of this view is the fact that 

 several wells driven by the same company subsequently^, for in^ivate par- 

 ties, at various points west of the Fish Commission wells, have not re- 

 sulted favorably, giving either brackish or muddy water. A well driven 

 for the commission on July 6, however, 47 feet deep, near the shore of 

 the harbor (G on the map) assayed (July 10) 20 grains of chlorine (cor- 

 responding to 33 grains of salt) to the imi^erial gallon, a rather larger 

 quantity than that afforded by the earlier wells. Otherwise the water 

 was similar to those previously examined. 



Since the present water supply of the Commission is from wells very 

 near salt water, and contains already a much larger proportion of salt 

 than ordinary spring water, it is a very important j^roblem whether the 

 water is likely to improve or deteriorate after prolonged pumping, and 

 whether the supi)ly is likely to run short. To test these questions a jiower- 

 ful steam pump was hired in Boston, and set up at Station F, on the 

 10th of June. After four hours' pumping, at a rate varying from 1,500 



* Water-bearing; strata. 



