Visit to the Siccirn Mountain 9. 
114 
[April 
plates transmitting the same, the numbers have only to be multiplied, according to 
Biot, by ,00023, which gives the result in inches. We shall have then 
No. 1 r = 0.00092 inch. 
„ 2 == 0.00254 „ 
„ 3 = 0.00396 „ 
„ 4 = 0.00575 ,, 
„ 5 = 0.00508 „ 
which agreed as nearly as might be with actual measurement. 
30. The measurement of thin crystalline plates is not the only useful purpose 
to which the polarizing instrument may be practically applied : a more important 
one is the ready means it affords of finding the axis of double refraction or crvs. 
tallization in any crystal, a main point in mineralogical crystallography, and in 
constructing what are called double image micrometers of crystal. ° It is useful, in 
a minor way, to detect false gems, without scratching them. It affords useful hints 
as to the best disposition of glass reflectors : but these are trivial matters ; the real 
point of utility gained bv the discovery of polarization, is the knowledge of a fun- 
damental law of light, which goes far to explain the rationale of reflection aud re- 
fraction two ro-existent elFects, which always seemed at variance with one another 
-—an attraction and a repulsion simultaneously at work on the surface of bodies:— 
it also gives very strong support to the theory of the materiality of light, and con- 
fiitns all the subtle reasoning of the great philosopher who first analyzed the prism, 
and pronounced the relative weight, number, and velocity of atoms, which, but for 
liis lesearehes, would, perhaps, never have been acknowledged to rrossess a material 
form or existence. 
II, — Particulars of a Visit to the Siccirn Hills, with some account of 
Darjiling, a place proposed as the site of a Sanatarium or Station of 
Health. By Captain J. D. Herbert, D. S. G. 
[Continued from page 96.] 
Darjiling is on the southern side of a great hollow or basin, hein^ that of the 
Ringit river, which falls into the Tista, a few miles east of the place. To the north 
the view is open, and exhibits the usual succession of range beyond ran^e all irre- 
gularly ramifying in every direction, and in apparently inextricable confusion. It 
terminates m the snowy range, which is here equally as magnificent an object as to 
the north-west, and there is some reason to suspect, includes peaks of even greater 
height than those measured in the surveys of Garlnval and of Kamaun. Unfortu- 
nately, during the two days we halted, the weather was unfavorable ; a mass of clouds 
almost continually obscured them, and it was only by an occasional glimpse of a 
peak that we were enabled to trace out their great extent, or guess at their superior 
elevation. r° he westward the view is confined by a lofty range at the distance 
of about 10 miles; intermediately is a low ridge connected with that of Gangla, 
winch is again a part ol the Smchal mountain ; on the top of this rid-e is the 
small village of Changtong, separated from Darjiling by a deen vallev° To the 
eastward appears the valley of the Tista, the bound arj of Siccirn and Sutan ; and 
on each side of it is the confused assemblage of mountain ridges as to the 
north. Above the head ol the Tista may be seen the opening of the Fe'ri pass— that, 
I imagine, by which Captain Turner visited Tashi Lumbu. To the left of it the 
high peak Chamattri, noticed also by that traveller, is visible • and west nf if the 
h’gliest : summit in this quarter, called Kanching-jinga. Tins’ is the peak which 
mentioned in a communication published in Bretvsterbi Edinburgh Journal and 
TlZoTet tiigh * V0,Can ° • 11 " S “ W t0 LaVe be “ and found to te 
To the south, Darjiling has the Sincliul peak, elevated about 9000 feet and the 
Gardan-kattar range, which is a ramification of it tIimp d ™ 
pletely clothed with forest from the top to the very bottom ”°! ,nta J ns ^ C ° m ' 
quent sameness of tint and want of break or variety in the surface^therS 
measurement, further 
b - Cn ab ’V° 3earn , any of the particulars of the 
rnan that it was in some degree only approximate nn d 
It is visible as a very conspicuous object from Dinaimir which leaus r, ff°rousIy ex ^ t ‘ 
miles distant in a direct line. This is, in itself In*"’,,*,- 3 ® annot bo k - ss than 150 
J in * presumption of great height. 
