404 



NATURE 



\Sept. 12, 1872 



Two thermometers, one of them an unprotected IMiillips, and 

 the other a protected Negrelti, were supplied by the Secretary to 

 Mr. Leboiir, as it was not certainly known at that timewhetlier 

 the bore was dry or wet. Mr, Lebour indeed beUcved it to be 

 dry, but nevertheless selected the Nejjretti thermometer, as it 

 was thought that the Phillips could not be read off accurately 

 with the poor light which in the position of this bore hole was 

 alone available. 



The following table exhibits the results of all the ob.servations 

 which have been taken in the bore, including three which were 

 taken in 1869, while the boring was going on. The boring w.xs 

 stopped, in the case of each of these three observations, only 

 about 20 minutes before the observations were made ; and the 

 heat due to friction appears to have produced abnormil eleva- 

 tion of temperature, amounting to about 2' at the depth of 2SS 

 feet, to about 6° at the depth of 5S2 feet, and to considerably 

 more than this at 85S feet. The other observations in the table 

 are Mr. Atkinson's, taken with the Negretti thermometer. 



The temperature 75° at the depth of 644 feet, a temperature 

 lower than either of the two between which it stands, was taken 

 on the first day of Mr. Atkinson's observations, and was con- 

 firmed by repeated triali at that time. This was the lowest 

 depth that could then be reached, the remainder of the boring 

 being apparently plugged up with "sludge." A spike was 

 subsequently attached to the thermometer case, which enabled it 

 to pierce deeper into the sludge ; but the lowest depth w'iich 

 could be reached (670 feet) is still far from the bottom of the 

 bore. 



It is intended to take a fresh s;rics of observations at every 

 50th foot of depth, and especially to re e.xamine the temperatures 

 at about 650 feet, where the reversal of temperature was 

 observed. 



The following are the rates of increase deduced from Mr. 

 Atkinson's observation--, omitting the temperature 75" at the 

 depth of 644 feet. 



r. Feet pel- deg. 



^,6 

 80 



50 

 40 

 62 



The average increase between the depths of 100 and 600 feet 

 is 1° in 5 1 '2 feet. These depths arc reckoned from the top of 

 the bore hole, which is 1,066 feet below the surface of the ground. 

 Mr. Lebour assumes that the temperature at the depth of 600 ft. 

 from the surface of the ground is \V. Accepting this estimate, 

 we have a difference of 295^° in 1,676 feet, (1,066 -^ 670-60 = 

 1676) which is at the rate of 1° in 57-5 feet. 



Mr. David Burns, F. G.S., reports that, from changes in the 

 management of the mines, and oilier causes, it has not been 

 possible as yet to carry out the dry observations at AUenheads 

 mentioned in last year's report. 



Only one other shaft has been met with at all suitable for 

 observation. It is called Brandon Walls shaft, and belongs to 

 the Rookhope Valley Mming Company, to the courtesy of whose 

 agent we are indebted for liberty to take observations. This 

 shaft is some 6 miles east of those reported on last year, and is 

 situated in the very bottom of Kookhojje Valle)-. The mouth is 

 covered over with a wooden shed, the shaft itself is free from all 

 obstruction, and the water in it has not been disturbed for some 

 ears. The shaft is m feet deep, and is full of water to within 



25 feet of the surfaje of the ground. Observations (by Mr. 

 Burns and Mr. Curry of Bolkburn) were taken in it on five 

 different days in July of the present year; but though agreeing 

 well with one another from day to day, they are so irregular that 

 they throw littl.': li^jht on the rate of increase of underground 

 temperature. At the depths of 83 and 133 feet from the ground, 

 the temperature was 4S'"5. In the ne.\t 50 feet there was an in- 

 crease of about 3°, the temperature at 1S3 feet being about 51 '4, 

 and from this depth to the bottom (an interval of 150 feet) the 

 temperature w.xs ncar'y constant. The best determination of 

 the temperature at the bottom w.as 51" 7. 



It maybe remarket that all nlnervations in shafts thus far have 

 exhibited irregulaiitics of this kind. The water in such large 

 openings seems to have its temperature governed by springs and 

 other extraneous causes, rather than by the temperature of the 

 surrounding so.l. 



The observations at every fiftieth foot of depth in the Kentish 

 Town well, as given in previous reports, are so complete that it 

 has not been thought necessary to continue them. A very deli- 

 cate thermometer, reading by estimation to the ijj of a degree, 

 has however been procured, for taking observations from year to 

 year at one constant depth (1,000 feet). It was constructed ten 

 months ago, and being enclosed in a partially exhausted glass 

 tube will probably not undergo much change of zero. It has 

 been four times tested by comparison with standards, and has 

 been found to have no error amounting to nearly so much as 0°'I. 

 m consequence of Mr. Symons' illness, no observation has yet 

 been taken with it in the well. 



A thermometer which, through the breaking of a rope, had 

 fallen into the mud at the depth of 1,090 feet hum the surface of 

 the ground, was extracted by Mr. Symons last November, more 

 than a year after its fill. It had sustained no damage, and its 

 indication when hraled up wa-! 6;)° 4, nearly agreeing with the 

 temperature previously observed at that depth. 



In addition to the large numbers of thermometers above men- 

 tioned as having been issued during the past year, one has been 

 furnished for observations which are to be made in the projected 

 boring through the Wealden and underlying strata. With the 

 exception otMr. .'Symons' observations at Kentish Town (London, 

 N.), we have as yet no observations of temperature from the 

 Southern piits of Lnglind, 



SECTION B— CiiE.Mic.\L Science 



Mr. Alfred Tribe read a paper On the Precipitation of Silver by 

 Copper. In the course of experiments made in conjunction with 

 the President, Dr. Gladstone, it was found that the silver 

 obtained by precipitating the metal from the nitrate by means of 

 copper always contained more or less of the latter metal. When 

 an excess of silver remained in a solution only minute traces of 

 copper were found, but as the silver solution became exhausted 

 the proportion of copper rapidly increased. This co- precipitation 

 of copper was shown to be due to the presence of atinospheric 

 oxygen. In one experiment as much as 15 per cent, of copper 

 was obtained after 48 hours exposure. When carbon dioxide 

 was caused to bubble through the solution during the precipita- 

 tion the quantity of copper deposited was greatly diminished. 

 The author showed an eudiometric apparatus in which this 

 property of absorbing oxygen was applied to determine the 

 proportion of that gas in the air. 



Mr. Gladstone gave a brief account of the physical and 

 chem'cal characters of the I'oleaiiic Dust recently ejected from 

 Vesuvius. In some localities the fall of this (lust was very 

 heavy and extended over a considerable area : the sample 

 cx.amined was collected at Ischia, upwards of twenty-five mdes 

 from the mountain. It consisted essentially of a mix'ure of 

 quartz and magnetite. No trace of titanium could be detected. 

 Dr. Thorpe stated that he had recently examined the Vt<lcanic 

 sand found in the neighbourhood of Etn.a, and its agreement in 

 chemical and physical properties with the sand from Vtsuvius 

 was very striking. It also contained no titanium. 



Dr. Schenck read a paper On tlie Amount of Pleat required lo 

 raise Elementary Bodies from the absolute zero io their state of 

 fusion. If we assume that a body at — 273° is completely deprivtd 

 of heat it is possible to calculate the total heat in it at any other 

 temperature provided that the specific heats of the body in its 

 three states of aggrega'.ion, its latent heats of fusion and vapori- 

 sation, and its melting and boiling points are known. Such cal- 

 culations a'e limited from the fact that only in the case of one 



