486 
NATURE 
[Oct. 13, 1870 
One of the Committee’s thermometers has recently been sent 
to Mr. John Donaldson, C.E., Calcutta, who has expressed his 
desire to aid in scientific observation, and being now engaged in 
examining for coal and iron under Government, is likely to render 
us effective service. 
Shortly after the last meeting of the Association, the secretary 
of this committee addressed a letter to Prof. Henry, secretary 
of the Smithsonian Institution, U.S., requesting his co-opera- 
tion in furthering the object which the committee have in view, 
at the same time forwarding one of our protected thermometers. 
In June of the present year an answer was received from Prof. 
Baird, assistant secretary in charge, to the effect that Prof. 
Henry’s ill-health during the present season had prevented his 
communicating to us the results of his labours in response to 
request. 
The letter addressed to Prof. Henry made special reference 
to an artesian well of extraordinary depth which was understood 
to be in course of sinking at St. Louis, and at the same time a 
letter was addressed, and a special thermometer sent, to Mr, C. W. 
Atkeson, the superintendent of the work of boring at St. Louis. 
No reply has been received from Mr. Atkeson, who appears to 
have left St. Louis before the letter arrived ; but letters have 
been received through the Smithsonian Institution from Dr. 
Chas. W. Stevens, superintendent of the County Insane Asylum 
at St. Louis, this being the institution for whose uses the well 
was sunk, together with a very interesting newspaper cutting, 
consisting of Mr, Atkeson’s report on the works. The boring 
of the well was commenced (at the bottom of a dug well 714 
feet deep) on the 31st of March, 1866, and was continued till 
the 9th of August, 1869;/vhen the work was stopped at the 
enormous depth of 3,8434 feet, exceeding by more than one-half 
the depth of Dukinfield Collery. The strata penetrated con- 
sisted in the aggregate of 63 feet of clay, 6 feet of coal, 380 feet 
of shales, 2,725 feet of limestone, and 620 fect of sandstone. 
A cast-iron tube of 134 inches bore was first put down, reach- 
inz from the top and secured in the limestone at the bottom. 
This tube was then lined inside with a wooden tube, reducing 
the bore to 44 inches. A 44-inch drill was put down through 
this tube on the above-mentioned date. Tiie bore was after- 
wards enlarged to 6 inches, and subsequently to 11} inches to a 
depth of 1314 feet. A sheet-iron tube was then put down, ex- 
tending from the top to this depth, and the bore below was en- 
larged, first to 6 and afterwards to 10 inches diamenter, to the 
depth of 953 feet. A sheet-izon tube, 79 feet long, was then 
put down, which rests on the offset at the bottom of the 10-inch 
bore. The 44-inch bore was then enlarged to 6 inches to the 
depth of 1,022 feet, and a wrought-iron tube of 5 inches bore, 
weighing more than six tons, was introduced, reaching from the 
top and resting on the offset at the bottom of the 6-inch bore, 
thus securing the work to this depth, and reducing the bore to 
convenient size to workin. The 44-inch bore has been continued 
to the depth of 3,843 feet 6 inches without further tubing. 
At the depth of 3,029 feet the first observation of tempera- 
ture was taken, and the reading of the thermometer was 107° F. 
This first observation is stated by Dr. Stevens to be specially 
worthy of confidence, as having been confirmed by several re- 
petitions, or rather, to use Dr. Stevens’s own wers, ‘this was 
the maximum of several trials.” It was taken, as well as those 
that followed it, by means ofa registering thermometer (kind 
not mentioned); but in answer to our inquiries, Dr, Stevens 
states, upon the authority of the carpenter who attached the 
thermometer to the pole by which it was lowered, ‘‘that no 
means were taken to defend the bulb from pressure.” In the 
absence of further information (and Mr. Atkeson himself has 
not yet spoken), we can place no reliance upon the temperature 
recorded, as the thermometer had to beara pressure of # of a 
mile of water. 
The temperatures registered at lower depths, the deepest being 
850 feet lower, were all, strange to say, somewhat lower than 
this, a circumstance which is all the more remarkable because 
the pressure (which tends to make the reading higher) must have 
increased with the depth. At the bottom, orrather at 3,837 feet, 
being 64 feet from the bottom, the temperature indicated was 
105°. ither of these results, taken apart from the other and 
compared with the surface temperature, would give a result not 
improbable in itself. The mean temperature of the air at St. 
Louis appears to be about 53°, but it seems desirable to ayoid 
publishing calculations till the data are better established. 
Unfortunately, the apparatus which was employed in boring 
has all been removed, after the insertion of two wooden plugs, 
with an iron screw at the upper end of each, one at the offset at 
a depth of 1,022 feet, and the other at the offset at the depth of 
953 feet, for the purpose of separating the fresh from the salt 
waters. These plugs were driven in with great force, and can 
only be withdrawn with the aid of a series of poles and other 
appliances, such as were used in the boring, which will be rather 
costly. ‘The poles alone are estimated to cost 1,152 dols., or 
about 200/7. If the plugs were withdrawn—and, according to Dr. 
Stevens, there is nothing but the expense to prevent—the whole 
well would be available for observation. The committee will 
ae every effort to prevent so rare an opportunity from being 
ost. 
The Secretary has also been in correspondence with Messrs. 
Mather and Platt, of Salford Iron Works, respecting a boring at 
Moscow, for which they have furnished machinery, and which is 
to be carried to the depth of 3,000 feet. They refer to General 
Helmerson, of the Mining College, St. Petersburg, as the best 
authority to whom application can be made for particulars of 
the Moscow boring as to temperature, &c. The secretary has 
accordingly written to General Helmerson, endeavouring to in- 
terest him in the objects of the committee, and offering to for 
ward thermometers. No reply has yet been received. » 
An element which it is necessary to know, with a view to the 
correct reduction of our observations, but which in many in- 
stances it is difficult to obtain by direct observation, is the mean 
annual temperature of the ground, at or near the surface. 
Instances frequently occur in which the temperature at the depth 
of 200, 300, or it may be 500 feet is accurately known, while the 
temperature in the superincumbent strata can only be guessed at. 
This is the case at the Kentish Town well, and partially at 
Rosebridge and Dukinfield collieries. 
It is very desirable that in connection with temperatures at 
great depths there should in each locality be an accurate obser- 
vation at the depth of from 50 to 100 feet. At such depths in the 
solid ground before it has been disturbed by mining operations, 
one observation suffices to give a good approximation to the 
mean temperature of many years. At depths of two or three 
feet it is necessary to observe, once a week, or so, throughout a 
year, in order to get the mean temperature at that depth for that 
year ; and this may differ by a considerable amount from the 
mean of a series of years. 
In the Report of the Scottish Meteorological Society for the 
quarter ending December 1862, there is a comparison of the 
mean temperature of the air with that of the soilat the depths of 
3, 12, and 22 inches, at four stations, from observations extending 
over five years; and in the Journal of the same society for 
the quarter ending December 1865, there is a comparison of the 
temperature of drained and undrained land from one year’s 
observations, undertaken for this purpose at two stations, and 
including also a comparison with the temperature of the year. 
The mean temperature of the air fer each day is, in these 
comparisons, assumed to be the simple arithmetical mean of 
the maximum and minimum, as indicated by self-registering 
thermometers 4 feet from the ground. From these observations, 
it appears that the mean annual temperature of the soil was in 
every case rather above that of the air, and that the excess was 
greater for sand than for undrained clay, and was greater for 
drained land than for the same land undrained. 
The greatest excess occurred in the case of the 22-inch ther- 
mometer at Nookten (Vale of Leven), where both surface and 
subsoil are sandy and dry, The five yearly means at this station 
were :—- 
Air 46° ; soil at 3 inches 46°3, at 12 inches 47°3, at 22 inches 
48:0 ; giving an excess of 1°9 for the temperature at the depth of 
22 inches as compared with air. 
The smallest excess, in the case of the 22-inch thermometers, 
obseryed for five years, was at Linton (East Lothian) where it 
amounted to 0°7 ; but the observations on the effect of drainage 
gave for the year of observation an excess of only 02 at the 
depth of 30 inches in light sandy but undrained soil under a rye- 
grass crop, at Otter House near Loch Fyne, the corresponding 
excess for drained land of the same kind and in the immediate 
vicinity being 0-9. 
The mean temperature at the depth of 3 feet at Professor 
Forbes’ three stations at Edinburgh, from five years’ observations, 
gave an excess of 0°55 above the mean temperature of the air at 
Edinburgh as determined by Mr. Adie’s observations. 
Observations on soil temperature in England are much needed, 
but the Greenwich observations give an excess of soil above 
air temperature falling within the limits above quoted, the excess 
