RANDOM NOTES ON NATURAL HISTORY. 



Magnetic Sand. 



Attention has been called in the Scien- 

 tific American to the Magnetic Iron Sand at 

 New Zealand, and we now quote largely 

 from an article b}' A. W, Brown, in tlio 

 Providence Journal^ relative to a similar 

 sand, covering a few acres in the vicinity 

 of the bathing-beach at Block Island. The 

 particles of magnetite in this sand do not 

 readily oxydize, and their brilliant faces re- 

 flect fiercely the light and heat of summer, 

 severely trying to the e3'es of one crossing 

 there, and giving the whole place, when 

 seen from a hill near by, the appearance of 

 a dark cloud swimming in a quivering at- 

 mosphere. 



This spot has been rented by New York 

 parties since 1868, and after many experi- 

 ments, they have been able to produce a 

 variety of iron of peculiar fibrous structure, 

 well adapted for placing between two pieces 

 of iron, as a thin film of glue is employed 

 between two pieces of wood, when the 

 parts are to be united with unusual strength. 

 This iron was called a " welding composi- 

 tion, ' and was sold for twelve cents per 

 pound. 



The sand is gathered on the beach in as 

 pure a state as possible and carted to the 

 place of separation, where it is dried, either 

 by the sun or b}'^ means of artificial heat. 

 From the dryer it passes hy gravity into a 

 large receiving bin, whence, by the buckets 

 of an elevator, it is raised and dropped into 

 a hopper having a long, narrow opening, 

 nearly over the centre of a cylinder, made 

 powerfully magnetic. All tlie non-magnetic 

 portion, influenced b}' gravity' alone, falls to 

 the ground, while the iron particles, at- 

 tracted by the cylinder, adhere to the mag- 

 netic surface. This nearly pure iron is 

 packed into bags containing 112 pounds 

 each. The separator, if properly fed and 

 run, is guaranteed to separate two tons per 

 hour from sand containing 33^ per cent, of 

 magnetic ore. It separates one ton per 

 hour with little care, and when working at 

 its best, with sand of a high grade, it has 

 delivered into the bags from four to five 

 tons per hour. The largest results given 

 were seldom obtained. 



The product is a purely magnetic ore, of 

 which several analyses show about the same 

 results as those given below, obtained by a 

 Brooklyn chemist from a sample taken at 

 random from one of the baffs : 



Magnetic oxide of iron 87.23 



Manganese oxide l.dc 



Magnesia • 0.72 



Lime 1.60 



Titanium oxide 4.10 



Silica 5.30 



100 00 



Mere traces were found of phosphorus and 

 sulphur. The metallization, or per cent, 

 yielded of actual iron, is marked at 63.15. 



A few words may be permitted in relation 

 to the amount of the Block Island deposit. 

 A careful examination has been made, holes 

 have been dug in several places to the depth 

 of from ten to fifteen feet, and the ground 

 sounded by iron bars nearly or quite five 

 feet further. In several places black sand 

 was found as deep as the holes extended, 

 and to the bottom of every hole the mingled 

 sand and cobble-stones of a beach forma- 

 tion, indicating that this part of the island 

 has probably been built up by the sea. 

 Encased in a rubber suit, Professor Jack- 

 son examined the bottom near the shore ; 

 and afterwards from a boat, he made care- 

 ful soundings over a large area, using a 

 strong magnet at the end of his line. For 

 a distance of two miles eastward from the 

 northern half of the island, the magnet in> 

 variably brought up magnetic ore, in some 

 places gathering enough to serve as an ar- 

 mature. It was estimated that fully a mil- 

 lion tons are readily available on land, 

 while on the bottom of the sea, perhaps at 

 a depth not too great to preclude the idea of 

 obtaining it profitably, there is a much 

 larger amount. Besides the sand which 

 the separator removes, there is a large 

 amount of black sand which is not magnetic, 

 but is still richly metallic. 



A New Volcano in Behring Sea. 



Sergeant Applegate, the signal-service 

 observer at Unalashka, Alaska, reports 

 that during the past summer a new volcano 

 burst out from the bottom of the sea, lati- 

 tude 54° north, longitude 168° west. " It 

 has been exceedingly active, as it has al- 

 ready formed an island from eight hundred 

 to twelve hundred feet high. According to 

 the report of Captain Anderson, the discov- 

 erer, who sails one of the Companv's ves- 

 sels, and who went wdthin two thousand 

 yards of it, it presents a magnificent sight. 

 The fire, smoke, and lava arc coming out 

 of many crevices, even under the water- 

 line. Large bowlders are shot high in the 

 air, which, striking the water, send forth 

 steam and hissing sound. 



