60 - -> -REPORT—1874, - 
after a course of about thirty miles, falls into Lough Neagh, and, passing through 
it, issues as the Lower Bann at the north end of the lake, was found to yield 13-4 
grains of solids, of which 10°6 grains consisted of mineral matters ; while in another 
ocality, about half a mile from the shore, the mineral matters were only 9°3 grains 
er gallon. 
‘ The water of the Upper Bann, except when it has been rendered impure by the 
numerous bleaching and other works on its banks, contains a very smal cies of 
mineral matters. A gallon on one occasion was found to contain only 4°614 grains 
of mineral matters, consisting of :— Sah Se LS i 
ee grains. 
Carbonate of lime... eee eee ee eee EES NEU Bie yee 1:239 
Sulphate of lime ........ SR Sov tga a aeehy enacts 1:354 
Oathonate of magnesia. (5.66 ies le. Pec eeba reese 0°622 
WVRIGG VOL ALO che eee ovccate sais, sole halos Gee 0:329 
Silicie acid ......... DAS DEERE AE ole ae 08s COWAB 
Chloride of sodium .,..... sip God ad bla lane eter nen eee 0-825 
4-614 
A specimen of the petrified wood weighing 26 ounces, in which the woody 
structure was clearly visible, and which was white on the outer surface and of a 
dark brown colour in the interior, when exposed to a strong heat in the crucible 
became black, and evolved an odour somewhat resembling that of burning wood, 
and by continuing the heat, left a pale buff-coloured residue. Contrary to what is 
stated by some authorities, the wood was not affected by the magnet before or after 
ignition. In no specimen has the author found the ash magnetic, 
100 parts of the specimen yield as follows :— 
Loss on ignition and organic matter ..........0e0eeeeeeeee 6°50 
Alumina soluble in hydrochloric acid .............0000 ee 0°68 
Oxide ofironkiyin) deurieen odd dec SEs ates eee are tie 0-04 
Lime ........ oe tbfele: dal eleient StiiNa ita. clot atolls ilatitn diotalsid Same Scie 0:29 
Magnesia ........cceeeeeee ahr crekeal ted ole REET. OBR 0:25 
Phosphorics@eidi isi ise’ vu.s ti. sears dealt be etteemane trace 
Alumina in state of silicate... cece cece eee e eens 1:95 
Lime ...... SSMS OaIER. pitetoke ats ARES aitttacce kolo, Gh BROS ae 1:10 
¢Mapnesiniys Yep aids loli a, xik. oseis lah Ot We AEE A SOE 0:25 
Bi Gie Meld heaters hidatal, yiwlalbs £00. betel ey oka 89-01 
100-07 
In another specimen from a different locality the loss on ignition was 9:1 per 
cent. It contained 84°5 per cent. of silica and only 1:5 per cent. of oxide of iron. 
and alumina. j ; 
The analyses, therefore, show that the water of Lough Neagh, in our time at least, 
possesses no peculiar qualities, and that the lapidifying material of the petrified 
wood is silicic acid and not oxide of iron. 
The examination of the specimens also clearly shows that the hardening is not 
roduced merely by superficial incrustation of the lapidifying silicic acid, but that 
it has penetrated through almost every portion of the vegetable structure, 
On the Composition of Tea and Tea-Soils from Cachar. 
_. By Professor Hopexs, M.D., F.C.S. 
Notwithstanding the important place occupied by the tea-plant in the dietary of 
so large a portion of the world, its chemical examination has attracted comparatively 
but little attention. We owe to Peligot and Mulder the most valuable investiga- 
tions which have been made in connexion with it; and more recently we have been 
supplied with some analyses of the ash of teas from the laboratory of Professor 
Horsford, while Wanklyn and Allen have lately contributed many facts of great 
