74 



KANSAS Academy of science. 



The well was found to be a bored one, cased with lumber. It was about eight 

 inches in diameter. Water is reached in this region at about 130 feet, but this par- 

 ticular well had been drilled much deeper. This fact had no influence on the blow- 

 ing of air, however, as other wells in the vicinity not over 135 feet deep show the 

 same phenomenon. The well is abandoned now, on account of machinery having 

 been lost in it which interferes with its use. 



On reaching the well, the writer first sealed the top, by means of mortar and plas- 

 ter of Paris, air-tight, inserting a one fourth inch brass tube to connect the well with 

 a gauge. The gauge consisted of a simple U tube of glass, bent so that the two limbs 

 were side by side. The bend of the tube, and for several inches up, was filled with 

 water, and a scale behind the glass tubes measured any difference in height between 

 the two columns of water. On connecting this gauge with the well, if air had been 

 blowing out, its tension was measured by the height to which the water in the outer 

 limb rose above that of the inner. If, on the contrary, air was being drawn into the 

 well, on attaching the gauge the water would stand higher in the inner limb. 



The following abstract from the observations made during four days will serve 

 to show the connection between the movement of air to and from the well and the 

 fluctuations of the barometer. 



August 27 . 

 August 27 . 

 August 27 . 

 August 27 . 

 August 27 . 

 August 28 . 

 August 28 . 

 August 28 . 

 August 28 . 

 August 28 . 

 August 29 . 

 August 29 . 

 August 29 . 

 August 29 . 

 August 29 . 

 August 29 . 



Gauge, 



milli- 

 meters.* 



29 



28 



23 



21 



16 







1 



2 







—31 



—33 



-31 



—30 



—24 



—17 



—10 



* The minus sign indicates a drawing in of air, the water standing higher in the inner limb of the 



gauge. 



The observations made showed conclusively that, the air of the well being sta- 

 tionary, if the barometer fell the air of the well at once exerted a pressure outward, 

 as shown by the water gauge. Should the barometer then remain stationary, the 

 tension of the air of the well became gradually less until equilibrium was again es- 

 tablished. As this well was closed by the gauge, the evidence was conclusive that 

 the tension was relieved by the escape of air from other openings, probably neigh- 

 boring wells. Equilibrium being established, should the barometer rise, the gauge 

 showed that the tension of the air of the well was less than that of the atmosphere, 

 and this ine(iuality was corrected by an inflow of air. If after a fall of the barom- 

 eter a rise should ensue before equilibrium was established, the gauge would still 

 show a greater internal tension; the well was therefore less delicate than the barom- 

 eter, because of the interval of time required for the necessary movement of the air. 

 After a sudden and considerable change of the barometer, a strong movement of air 

 to or from the well would be caused, and this movement would continue for some 

 hours, even though the barometer might be slowly returning to its original height. 



These wells doubtless tap a subterranean reservoir of air, probably filling the in- 

 terstices of sand or gravel beds. When the pressure of the external air is dimin- 



