78 DESTROYIXG DERMKSTIDAE. 



here used, but reckoning it at fifteen feet would give a thousand and 

 sixteen feet as the length, and four hundred and twenty-five as the 

 breadlli of this chamber. And nothing but the marly rock as its roof ! 



A singular apparatus is employed down at tlic foot of the mountain 

 for measuring the amount of brine tapped from these chambers. Two 

 large vessels, about the size of hogsheads, are attached to the ends of a 

 beam that swings upon a pivot. The water, led down the side of the 

 mountain in pipes and falling into one of these vessels, gradually bears 

 it downward until, just as it is completely filled, it strikes a projecting 

 rod that opens a valve in the bottom of the vessel, and it commences at 

 once to discharge its contents into a reservoir below. The same instant 

 the current of brine is turned into the other vessel, which is filled and 

 sinks as the first is emptied and rises. And thus the see-sawing process 

 incessantly goes on, the number of oscillations being marked, like the 

 turns of a reel, upon a dial-plate attached to the apparatus. Thus the 

 brine is made to measure itseli". The beams and wheels of this appara- 

 tus become encrusted with a deposition of crystals from the salt water 

 as it trickles over them. I broke off' some and observed that here it 

 always assumed the form of the cube, and was perfectly opaque and 

 white ; whereas the minute crystals I had procured up in the mountain 

 were hexagonal and variously truncated and perfectly transparent. 



From the large reservoir the brine is let ofi' to the pans, or caldrons, 

 as fast as it is needed. These are not more than about a foot deep, but 

 at least fifty feet in circumference. A constant fire is kept up under these 

 for two weeks at a time. The salt crystallizes rapidly, and is scraped 

 to the sides of the pan and sliovelled out into baskets shaped like the 

 mould of a sugar loaf, and just large enough to hold one hundred pounds. 

 Night and day one set of hands succeeds another, and fresh brine is let 

 in as fast as the old disappears. Clouds of vapor incessantly pouring 

 forth from the blackened roofs shows what becomes of the mountain 

 water that had been let into the chambers above, fresh and pure ; tons 

 of table salt stowed away in the imperial storehouses, account for the 

 saline treasures of which the mountain has been robbed ; and upon the 

 iron plates of the caldrons are deposited the other mineral substances 

 that had been held in solution by the brine before its evaporation. 



A NEW WAY OF DESTROYING THE DERMESTIDAE IN COLLECTIONS 



OF INSECTS. 



Naturalists in all ages have complained that their Collections were 

 constantly attacked by the larvae of small beetles, and sometimes of 



