228 



SCIENCE 



[N. S. Vol. XXV. No. 632 



TABLE n. HOURLY BAKOMETRIC READINGS, U. 8. 



WEATHER BUREAU, CHATTAJTOOGA, TENN., 



DECEMBER 21 TO 26 INCLUSIVE 



Boston Well. — The Boston deep well be- 

 longs to the second class of blowing wells, 

 namely, wells in which the direction of the 

 air current is in one direction only. Boston, 

 the town in which the well is located, is on 

 the Atlantic Coast Line Railroad, in the 

 southeastern part of Thomas County, twelve 

 miles east of Thomasville. It has an eleva- 

 tion of 198 feet above the sea-level. The sur- 

 face of the surrounding country is compara- 

 tively level, though lime sinks, produced by 

 the subterranean stream, are occasionally met 

 with. The prevailing rock of the region is 

 Vicksburg-Jackson limestone overlain by 

 sands and clays of variable thicknesses. 



The well, which is six inches in diameter, 

 has a depth of 290 feet. Water was reported 

 at 120, 160 and 286 feet, respectively. The 

 main water supply at present is said to come 

 from a subterranean stream in the limestone 

 at 120 feet. The easing extends to 110 feet. 

 The static head of the water in the well when 

 completed was 128 feet from the surface, or 

 eight feet below the subterranean stream. 

 Shortly after the completion of the well, Mr. 

 J. Z. Brantley, the mayor of the town, dis- 

 covered that there was a continuous draught 



of air passing down the casing, and by placing 

 his ear near the mouth of the well he was able 

 to detect a sound like running water. This 

 indraught, Mr. Brantley reports, was quite 

 strong and continued as long as the well was 

 left open. The writer was unable to verify 

 Mr. Brantley's statement at the time of his 

 visit, owing to the well being connected with 

 the pump which supplies the town with water. 



The Lester Well. — This well, reported by 

 William Miller, which is also similar to the 

 Boston well, occurs on B. E. Lester's planta- 

 tion, twenty miles south of Thomasville, near 

 lamonia Lake. Mr. Miller, in describing this 

 well, says that at a depth of 154 feet he struck 

 a stream of water running so swiftly that he 

 could not pass a two-pound iron plumb bob 

 attached to a fishing line through it. He re- 

 ports blowing crevices in the well at 87, 124 

 and 144 feet. When the well was being bored 

 the air from each of these cavities is said to 

 have passed in in the forenoon and out in the 

 afternoon; but after the completion of the 

 well to the swift moving subterranean stream, 

 the air ceased to pass outward, but was sucked 

 in with a strong steady pull, drawing the 

 flame and smoke of a torch down the casing 

 when held six inches above its opening. This 

 well is cased to YO feet, below which point it 

 is said to penetrate a soft white limestone. 



Causes of Blowing Springs and Wells. — The 

 two classes of blowing springs and wells above 

 described appear to be due to two entirely 

 different causes. Those of the first class, of 

 which the Grant blowing spring is a good 

 type, seem to be due entirely to the difference 

 of atmospheric pressure of the air on the out- 

 side and on the inside of the cave. 



At the time of my visit to the Grant blow- 

 ing spring, I was of the opinion that the 

 relative temperatures of the air on the out- 

 side and on the inside of the cave, the latter 

 temperature being indicated by the water 

 flowing therefrom, had something to do with 

 the air currents; but the record furnished by 

 Mr. Grant (see Table L) shows that the direc- 

 tion of the currents has nothing whatever to 

 do with these relative temperatures. That 

 these currents are due solely to the variation 

 of atmospheric pressure appears to be con- 



