SCIENTIFIC NEWS. loj 



are found. Some are entire, and very large : others are ag- 



j>Uitinated as by a cement. Some are iaige enough to cpa- 



tuiia a man's foot. In different parts of the emiaences for 



forty miles some of these sliells occur. They are used ror 



makiijg hme ;. but a Uttle hi^her up to the south-west there 



a heap of shells forming a kind of rock, that is preferred 



-1 this purpose. At some distance still higher, and in the Fossil shells in 



same direction, there are several quarries of a kind of sili- * 



ceous stone, in which a great number of shells of all kinds 



are interspersed here and there. These are petrified, and ^^^^ ^^ ^"^** 



as hard as the flint itself. Millstones are made of it, in qua-^^^ljsto^es 

 1- ,1 , n TT made of it. 



lity nearly the same as those or r ranee. 



At Hudson's Bay some experiments have been made with Quicksilver ■ 

 frozen mercury. It was reduced to a plate as thin as paper, ^^^^j^ plate, 

 by beating it on an anvil with a hammer brought to the same 

 temperature as the mercury. A piece of it being thrown 

 into a glass of hot water, the water froze instantly, the glass 

 flew to pieces, and the mercury became fluid. 



Dr. Bacoaio 'of Milan has lately composed a galvanic 

 pile entirely of vegetable substances. He forms it of disks 

 of red beet root, two inches in diameter ; and disks of wal- 

 nut tree, of the, same size, divested of their resinous princi- 

 ple by digestion in a solution of cream of tartar in vinegar. 

 With this pile he produces galvanic efl'ects on a frog, taking 

 a leaf of scurvy-grass for an exciter. 



THE seventh number of the new series of the Mathe- J;^atl^ematicaJ 



Kepository, 

 matical Repository, by Mr, Thomas Ley bourn, contains : 



1. Solutions to thirty curious mathematical questions pro- 

 posed in a former number; 2. Solutions to some mechanical 

 problems by Mr. John Dawson; 3. Solution of a curious 

 diophantine prob*jem by Mr. Cunliflc ; 4. An essay on the 

 theory of amicable numbers by Mr. JohnGough; 5. An 

 investigation of some theorems for finding the sums of cer- 

 tain infinite series b}^ Mr. Cunliffe: 6, Le Gendre on elliptic 

 transcendentals : and 7. Thirty new questions to be an- 

 swered io a subsequent number. 



Mr. 



