292 Vn the Gypsum of the Himalaya. [July, 



the bed of a tributary that joins the Nagul stream, opposite the 

 village of Salkofh. The whole mass is composed of gypsum, 

 without the intervention of any alternating rocks ; and a conclusion 

 may naturally be drawn from the absence of the mineral in its 

 vicinity, that this deposit is insulated, or simply an enormous nodule, 

 resembling those of calcareous tufa so frequently met with, in de- 

 tached and unconnected masses. The falling down of large masses of 

 the upper part of the rock has caused such confusion and irregularity 

 below, that it would be even doubtful whether the deposit actually 

 extends to the bed of the stream, or whether its limits might not 

 properly be curtailed to a depth of at least one-half, a circumstance 

 moreover that precludes the possibility of discovering the rock on 

 which it lies, or of satisfactorily describing the concomitant forma- 

 tions. The same difficulty generally occurs with these rocks; their 

 decomposition is universally great, and the extreme variableness 

 in texture so open to the attacks of weather, that externally, with- 

 out the aid of slips and fractures, it is almost impossible to detect 

 any regularity in stratification, or in fact any clue wherefrom to 

 form an idea of their general character. The tendency that this 

 rock has to form itself into peaks and protruding points is well 

 preserved here, and deserves mention from a peculiarity for which it is 

 distinguished in the Alps; resting solely however upon the decomposing 

 character of the rock, and from no material form of composition. 

 The mountain itself is formed entirely of the blueish limestone former- 

 ly mentioned, into which the gypsum decidedly passes, modifying 

 itself into a blueish variety, effervescent, and differing only in ap- 

 pearance from the limestone itself, by its want of compactness, and 

 loose and friable quality : a black fragmentary and argillaceous lime 

 rock is also in abundant dissemination throughout the lower part of 

 the deposit, and singularly attached to those parts where the gypsum 

 appears to be of a purer quality than at others ; indeed it generally 

 appears that by the presence of the rock in question, the mineral ac- 

 quires a purity both in color and texture, unobtainable in those parts in 

 contact with the blue limestone or at a distance from the black 

 rock. It would be endless to enumerate the colors that appear 

 throughout this formation ; from the purest white crystalline, it 

 passes through dirty grey pink, until it arrives at the blue limestone, 

 when it obtains a tinge of that color. The texture is also as variable, 

 and I may say, that throughout the whole deposit a very small propor- 

 tion is of that variety generally known by the name of alabaster ; and 



