Intelligence and Miscellaneous Articles. 237 



steps of stones to a stage of ten feet high, and is in a south-east di- 

 rection. Here the roof begins to form a regular arch, the height of 

 which from the floor vaxies fi'om five to eight feet, the grotto being 

 from six to twelve feet wide, to the part called the crawling place, a 

 name which is given to it in consequence of travellers being obliged 

 to crawl, in order to reach another large neighbouring chamber ; 

 from this to the spot, in which a pillar is found, for a mile and a 

 quarter, there occurs an alternating succession of large and small 

 chambers. Sometimes the way is flat, at other times enormous 

 blocks of rock must be climbed, which have been detached from the 

 roof, and then the pillar occurs in the form of a magnificent white 

 column, which reflecting the sombre light of the torches, has a 

 majestic and dazzling aspect. Visiters rarely proceed further than 

 from 100 to ISO fathoms. The pillar or column is 15 feet in dia- 

 meter and thirty high ; it is regularly fasciculated from the summit 

 to the base. Not far from it are several other pillars of the same 

 form, but of smaller dimensions : it is composed of carbonate of 

 lime. 



The date of the discovery of this grotto is not known ; it is known 

 only that it was visited in 1807 by some persons who found in it a 

 bed of salts from 6 to 9 feet thick on the bottom of the grotto, where 

 they observed enormous blocks scattered over it, whilst the walls 

 were covered with saline products. The sulphate of magnesia abounds 

 throughout this grotto in difi'erent forms, and sometimes in masses 

 of one pound to ten. The soil has a brilliant appearance on account 

 of the numerous portions of this salt disseminated in it. This sul- 

 phate lines the walls at various distances ; if it be removed it is re- 

 produced in four or five weeks in needle-form crystals. The poorest 

 earth which has been washed gave four pounds per bushel, and the 

 richest from 20 to 25 pounds. The salt which next occurs in the 

 greatest qiiantity is nitrate of lime, and aftervi'ards nitrate of alumina, 

 which yields as much nitrate of potash as the nitrate of lime. Sul- 

 phate of lime also occurs, with traces of sulphate of iron and of car- 

 bonate and nitrate of magnesia. The sulphate of magnesia is not 

 pure, as will be readily conceived. — Journal cle Chmiie Medical, 

 January 1840. 



MANUFACTURE OF CHLORATE OF POTASH. 



M. Pelouze has communicated a new and advantageous mode of 

 preparing chlorate of potash. Hitherto carbonate of potash has 

 alwaj's been decomposed by chlorine : M. Pelouze describes the in- 

 conveniences of this process, which he proposes to remedy by sub- 

 stituting soda for potash ; by this chlorate of soda and common salt 

 are obtained, and the chlorate of soda is converted by double de- 

 composition in chlorate of potash by one of the cheap salts of pot- 

 ash which occur in commerce. 



M. Pelouze also proposes to pass chlorine into milk of lime, by 

 which chloride of lime is obtained, and this is then decomposed by 

 chloride of potassium. — L'Institut, No. 318. 



