728 PROF. J. W. JUDD ON THE NATURE AND RELATIONS OF 
to change the method of boring; the old machine was taken down, 
and a rotary diamond rock-boring machine erected in its place. 
This last machine has carried down the bore-hole with a diameter 
of 83 in. from 1337 to 1367 ft. 6 in., at which last depth, lining 
tubes having to be aniserued the diameter of the bore-hole was 
further reduced to 77 in., with which diameter it has now reached 
the total depth of 1409 ft. The cores obtained from the last 72 ft., 
being large and solid (from 5 to 6 in.in diameter), enable the dif- 
ferent dips of the strata to be very accurately determined. These 
cores too show the rocks to be of much the same character as when 
these Red Sandstone beds were first reached. | 
The bore-hole is now lined with strong iron tubes down to the 
depth of 1364 ft. ; those portions of the tubes that are in proximity 
to the different depths where water was struck, are drilled with holes 
to admit the water into them. 
Unfortunately, till the depth of 1337 ft. was reached, time could 
not be spared to make accurate observations as to the rise in tempe- 
rature as the bore-hole was deepened; but the following table serves 
to show that the water at the different depths named had the tempe- 
rature of deep-seated springs :— 
Date. Depth from Surface. Degrees Fahr. 
: ft. in. a 
Heb, PAth GSS) fescec dees. 1149 « .Giyucet eee 69 
Marchvaatin ® Ga. cespscone LATS. 70 cee 70 
Atyeulaiie te, Aste ot 1195 0. "See 73 
Appraltatst® 4p +" 1. cake e, 1212) }O" 2. 73 
The above are not the true temperatures at the depths named, 
but were ascertained by the following rough method:—A round 
vessel nearly the size of the bore-hole, having a valve at bottom 
opening upwards, was lowered to the bottom and brought to the 
surface.- The valve of the vessel closing directly the winding-engine 
was reversed, collected the water from the bottom of the bore-hole, 
and the temperature of the water so collected was taken when the 
vessel had reached the surface. The raising of the water to the 
surface only occupied two or three minutes. 
The three following observations on the temperature of the bottom 
were taken when the bore-hole had reached the depth of 1337 ft. 
below the surface. The bore-hole was full of water and Ove 
at the rate of from 3 to 4 gallons a minute. 
In all three cases it is clear that the results obtained are free from 
any error due to heat generated by the friction of the tools during 
the process of boring, as the results are identical, and in No. 1 there 
had been a cessation of boring operations for 3 weeks, in No. 2 for 
4 weeks, and in No. 8 for 13 weeks. 
In the first two cases the thermometer was simply lowered, and 
left in No. 1 for 1} hour, and in No. 2 for 54 hours; in both cases 
the temperature registered was 754° Fahr., the temperature of the 
air at the surface being respectively 51° and 53° Fahr. 
In No. 3 the thermometer was lowered inside a wrought-iron 
