68 
Report—1854. 
although In these cases no corresponding radial structure of the matrix was found io 
exist. Alter having entered into this subject ut some length and drawn the attention 
of the section to these points of what may be termed “ Geological Mineralogy," the 
study of which was insisted upon as of great importance in elucidating the formation 
of minerals in nature, the author proceeded to the chemical examination of tin* 
minerals, specimens of which were shown, and the results as well as the methods of 
chemical analysis employed in the examination of several of these minerals were 
detailed. 
Several new minerals were shown, which lmd been examiued and named, and which 
were found to contain some of tho rarer metals and earths, and the properties of 
these bodies somewhat commented upon. 
On the Heating Effects of Secondary Currents. By J. P. Gassiot, F.R.S. 
In January last Mr, Gassiot communicated to the editor of the Philosophical 
Magazine ah account of experiments made with RuhmkoWTs induction coil, a» d 
alluded to the fact, that the heating effect, which had already been noticed by M«*°n. 
took place in the contrary direction to that which is produced iu the primary current. 
Which heating effect had been observed as far hack as 1838. Since January l«»h 
Mr. Gassiot has hud several forms of apparatus constructed for the purpose o' > ■ 
serving the pluenomonu of secondary discharge in relation to its heating effects — 
, l , discharge of the secondary current takes place in air the negative jemum 
(which in these experiments was of plutina wire) became heated, L'. Iftw Hir ' 
are sealed into small fthermoineter'l straight tuhii.tr. neither terminal BPprars tn no 
wlitni. . 1 UL 1,1 an « ones tne piatmn wire t excepi*iu»“> ,i iC 
T ere<1 wil, ‘ « minute black deposit. At this terminal, whenj^M 
H ow • 18 ,n i u e ’ a mitthte but hrilliunt spark appeals, from which the e ec f i[. 
know, if Pat fl bt,imt} nnd brilliancy. The negative is at first covered with the 
*■»« V n,il !t »*«»»« red-hot; no deposit appears to remain « » 
exhau •tedV» m,,,U ’ ‘i al * 1,le experiments made with closed glass tubes, the 
exhausted by means of an a»i-p„mp. 
0,1 a Metho f f Analysis applicable to the Quantitative Estimation offfl* 
and Acetic Acids. By J. H. Gladstone, Ph.D., F.R-S- # 
verv I, l«M?m° d p . ropo ^ ,,J consisted in distilling the substance to be onaksed ^ 
stilinte in ° f su P^ ur,c nc ‘*l >» a retort, and in collecting the c °". )W( j;!v 
converted infnT er . COIIt ‘! ,ni ' 1 '’ water nnd carbonate of baryta, 't he ' ICI L\ nt rf 
processes V 80 f * l ^ e amount of which can be estimated bj r j me nt 
were described* 1 " T? precnutioh8 requisite for the proper conducting ° nhe ^P ] I ( r 
vet as bei, e Jr" ,f 0Ce * 9 Emitted, not W 'involving any new P™ c J f lW d 
to be c-S,t bAv CUy 1H ' CUrat0 n ' ethod ’ but as one which the author bad 
ercoming one of the difficulties in practical analysis- 
On the Fluorescence exhibited by certain Iron and Platinum Salts- 
■/ ‘b Gladstone, Ph.D., F.R.S. 
