TRANSACTIONS OF THE SECTIONS. 
49 
ble action to countenance such an explanation; and its ready solnbilit}' in acetic 
iot shows that it is not caused by sulphates, unless in so fur us it is not dissolved by 
tuiacid. The ordinary cause I have ascertained to be the presence of carbonate of 
hie; but the remarkable fact is, that the reaction both of the acetate and of the acetic 
cidubes place even after the water has been boiled and hUered, lo that carbonate 
lime remains dissolved indcpendenllv of llie presence of carbonic acid. The waters 
aferred to yield carbonate ot lime w&cn uraporuted after having been boiled and 
S<ered. 
To aswtaiii whence this carbonate of lime has proceeded, 1 passed a current of car- 
laic add throueh lime-water, till tlie precipitate at first formed was redissoived, and 
tea boiled and filtered the liquid ; but it did not affect lead salts to the same extent 
• common waters do : neither did distilled water which had been left some days in 
BBtset with finely pounded marble. 1 incline lo think that the origin of thu dis- 
■h«l carbonate of lime is double decomposition between an alkaline carbonate and 
tidubic lime-salt; and have found,in all waters yielding the reaction, alkalies united 
The common water of the town of St. Andrew's contains -rtizTi of carbonate 
• Iiifle, after being boiled and filtered, ll also conttiins a trace of carbonate of niag- 
which substance may also occasionally bo in part tbc cause of the reaction 
•tcfted to, aUbuugh to a far less extent. 
Sulpliaio-Ckloride of Copper—a new Mineral. Gy Professor Connell. 
Amoog iome minerals which were lately put into my liatids by Mr. Brooke for 
*cniiciu examination, there was one which 1 found to consist of sulphuric acid, 
lonne, copper and a little water. Although I had not enough material to determine 
cproportlonsoflhe constituents, there can be no doubt that it consists of sulphate and 
ill' K with a little water. It occurs in small but beautiful fibrous crystals, 
iV to Mr. Brooke, are liexagnnal prisms having the angles replaced, 
. helong to the rhomboliedral system. Their colour is a fine blue, pale when 
breg are delicate, but much deeper whero lliey become thicker. Lustre vitreous, 
Muesnoy considerable. Locality, Cornwall. The mineral is associated with arse- 
of copper. Few specimens are at present known: one is in the British Museum. 
^ iVMft-iViVe Value of flifftirent kinds of Food. JSy Prof. Daubeny. 
^. Duubcoy bad intended, before the stato of his voice precluded him from much 
before the Section, in detail, his view* with regard to the uutritivo value 
mat kinds ot food, as compared with their commercial price, in order to establish 
tetl ®f*tl to remove certain popular errors on this important subject. Ail 
^erhecould now attempt to do, waitn direct the attontion of the meeting to three 
T«‘u«pcnded in the room. The first of these was intended to show the commercial 
^ .!• pi'paent prices of the same weighu of wheat-flour, of oatmeal, of potatoes, of 
^Iv of meat, 'fhe second table was aii attcm]it to stale nuiiie- 
® relation between the proportion of nitrogenized and non-mlrogcnized 
llhe substances as compared with their coinmercial value estimated 
■5i»er I * in the preceding laole, from which it appeared that if the nu- 
. Tfliuc ofwheal-flour he stated at 100, and its hcat-producing power at S4-5, an 
former will be 70 and the latter 100, whilst the commercial value 
from 2 
■" s miiarcalciUations made with respect U 
100 . 
- - --respect to Indian com, it did not appear that 
riatinl the ground of furnishing more nutritive or heat-produemg 
'r re£i” wheat would do, although tlierc may be other reasons 
adoption. The third tabic professed to g;ve the 
hon-nitrogenized principles calculated to exist in the food 
'''•kraH.l . ^ convict daily m Uie Pcntonville prison, after several successive 
»nJ ^ quantity necessary for sustaining an adult ui a stale of 
diminulion of his weight. From this it would appear, that about 
" *^SCRi*od principlM, namclv of albumen, caseme, orfibnne were 
a nutrition of an ordinary adult daily, and that of non-nitrogenized 
quantity sufiicient to supply 7^ " * - --- 
ounces of carbon for respiration must be 
E 
