32 Sir John F. W. Herschel's Chemical Examination of 



grees of saturation, with which the following experiments were 

 tried. 



\st Expeyliuent. — Haifa pint of saturated brine sp. gr. 1216, 

 temperature 82*5 mixed with about the same quantity of brine 

 of sp. gr. 1069, temperature 81*2. Result, temperature 82-2 

 and no effervescence after standing some minutes. 



2nd Experiment. — Same quantities of brinesp.gr. 1216, 

 temperature 82-5, and of brine sp. gr. 1091, temperature 81°. 

 Result, sp. gr, 1 152*5, temperature 82*2 and no effervescence. 



Srd Experiment. — Same quantities of brine sp. gr. 1216, 

 temperature 82-5, and sp. gr. 11J5, temperature 81-6. Re- 

 sult, sp. gr. in-t'S, temperature 82*1 and no effervescence, 

 nor anj' increase of temperature after remaining some hours 

 in the glass. 



Being therefore quite unable to offer any explanation of the 

 cause of the remarkable heat observed in my brine reservoirs, 

 I can only promise to register the temperature from time to 

 time when they are filled again, in the hope that materials 

 may thus be furnished to some scientific friend more capable 

 of solving the interesting problem. If it should be discovered 

 that a slow fermentation arising from the mixture of brine of 

 different densities in large masses is the cause of this heat, it 

 would seem to be accelerated by agitation, for the water raised 

 by the pumps was always warmer than that which the probe 

 brought up from the same depth ; and, except at the first 

 trial at Narainpore, always hotter than the maximum given 

 by the probe. 



VI. Notice of a Chemical Examination of a Specimen of 

 Native Iron, from the East Bank of the Great Fish River.) 

 in South Africa. By Sir John F. W. Herschel, Bart., 

 M.J., F.R.S.f' 



nPHE [portion analysed of the] specimen in question weighed 

 originally 21*79 grains, 5*12 of which were separated, and 

 submitted to a hasty preliminary examination for the detection 

 of nickel, if any ; but the quantity proving too small, the whole 

 of the remainder was operated on in a subsequent trial. 



The iron was highly malleable and tenacious, and appa- 

 rently of excellent quality, with a somewhat whiter and more 

 silvery lustre than belongs to the metal in its ordinary state, 



* Read before the Literary and Scientific Institution of South Africa : 

 now extracted from Sir James E. Alexander's " Expedition of Discovery 

 into the Interior of Africa." Lond. 1838, vol. ii. Appendix, ]). 272. The 

 s|)ecimen had been found by Sir James Alexander, and presented by him 

 to the Institution. 



