321 



M'\ Alger alluded to the sudden disappearance of young ducks 

 in ponds. A friend of his who had several about a week old, was 

 surprised to see some of them suddenly pulled under water. He 

 discovered that they had been seized by Snapping Turtles, {Ejny- 

 savrus sciyentina.) It is a common belief that Bull Frogs are 

 guilty of the same misdeeds. 



At the request of Mr. Alger, Dr. C. T. Jackson gave a 

 description of the 'red oxide of Zinc and Frankliuite found 

 in large beds in Sussex, Sterling, and Franklin, N. J. ; to 

 which localities they had recently made a visit. 



This mineral will be valuable for many purposes ; but princi- 

 pally for the manufacture of the white oxide, or zinc white, 

 which may be so advantageously substituted for white lead as a 

 paint, thus protecting workmen from the well known poisoning 

 of tlie system caused by the latter. This has till lately been 

 imported, but now an inexhaustible supply has been found at 

 home. This mineral consists of oxide of iron, manganese, and 

 oxide of zinc. 



The advantages of this as a paint over vv'hite lead, in addition 

 to the security of the workmen from disease, are, that the action 

 of gases will not change it, while lead paint is turned black by 

 sulphuretted hydrogen ; it is perfectly white, and gives to a 

 surface the lustre of porcelain. The Astor Flouse in New York, 

 and Mr. Alger's house in this city, are painted with Zinc white. 

 It is ground in spirits of turpentine, and mixed with varnish to 

 give it consistence. 



Frankliuite alone makes an excellent grayish-brown paint, 

 very permanent, and drying quickly. The red oxide of zinc 

 also makes an excellent quickly drying red paint. By adding 

 lamp black, prussian blue, &c. several shades of color may be 

 readily obtained, free from the disadvantages of lead. 



Franklinite is also used to purify iron, and to render it tough 

 and fibrous, by freeing it from sulphur and phosphorus. 



A donation of living specimens of Trionyx ferox and 

 Emys insculpta was received from Rev. Zadock Thompson, 

 of Burlington, Vt. 



PROCEEDINGS B. S. N, II. 21 DECEMBER, 1850. 



