Intelligence and Miscellaneous Articles. 73 



Perhaps the form in which the salt has formerly existed in this case, 

 as indicated by the cavities, may be regarded as throwing some light 

 on the history of the new-red-sandstone. The presence of the hop- 

 pers, and especially their occurrence in greater numbers than the com- 

 plete cubes, if we may be permitted to reason analogically from the 

 artificial crystallization of salt by the evaporation of brine or of sea- 

 water, indicates the existence of an elevated temperature, during the 

 formation of the including strata and the deposition of .their mineral 

 contents. In the manufacture of salt in Cheshire, it is observed, that 

 the hoppers are formed by the rapid evaporation of the saturated 

 brine at a temperature of from 160° to 170°, Fahr. j and that the 

 distinctness and perfection with which cubic crystals are produced, is 

 in the inverse ratio of the temperature applied and the consequent 

 vapidity of the evaporation ; salt made at 130° or 140° first approach- 

 ing to the distinct cubic form, and that made at 100° or 1 10° being 

 in large and nearly cubical crystals*. The hoppers, indeed, appear to 

 result, exclusively, from the evaporation of solutions of salt at a high 

 temperature. 



May not these facts, therefore, notwithstanding Dr. Holland 

 (Trans. Geol. Soc. vol. i. p. GO.) has thought proper to exclude the 

 agency of heat from the formation of the deposits of salt, be consi- 

 dered as corroborative of the opinion that the new-red-sandstone con- 

 sists of the debris of the older rocks, which, partially in a state of 

 minute division, and preserved, either wholly or in part, in a humid 

 state, by the waters of a primaeval ocean, have been as it were torre- 

 fied by the agency of heat acting from below ? The peroxidated form 

 of so large a proportion of the iron which it contains, and the evident 

 injection from below at some distant period, in a state of igneous 

 fluidity (or, to speak with caution, in a state similar to that of fresh- 

 erupted lava) of the masses of porphyritic trap with which it is often 

 intersected, are also circumstances which tend to strengthen this opi- 

 nion. 



Another fact observed in the manufacture of salt may perhaps be 

 regarded as tending further to elucidate this subject. Although, as 

 just remarked, the hoppers appear to result, exclusively, from the eva- 

 poration of solutions of salt at a high temperature, yet they are not 

 formed when the brine is at the boiling point. At that heat, as may 

 be observed in the process of making stored or lump-scdt in Cheshire, 

 and in those by which salt is chiefly made in Scotland and at Lyming- 

 ton, small flaky crystals only are deposited, merely approaching in 

 form to an irregular pyramid with a square basef- The occurrence 

 of the hoppers, therefore, in, the saliferous rock, indicates that the 

 heat to which the solution that deposited the crystals was exposed, 



is " mixed with salt in small |)atclies aiul cubes." If water were to perco- 

 late slowly through this bed, the salt would he dissolved, and cubic and 

 other cavities left in the nuirl, if of a texture sufTu-ienlly coinpuct, which 

 would then present a siniilar aiipearance to the hcds described above. 



• Sec Dr. Henry's paper in I'hil. Trans. ISIO, Sic. 



+ Sec Dr. Holland's Report on the Agriculture of Cheshire, p. 5.T; and 

 Dr. Henry, in I'liil. Trans. IHIO. 



N.S. Vol . G . No. 3 1 . Jith/ 1829. L was 



