696 



THE POPULAR SCIENCE MONTHLY. 



write the name of the deceased cretin across 

 the forehead of the siiull, to paint a fillet 

 of leaves and flowers around the latter, and 

 to engrave on it different emblems, as cross- 

 es and the like. 



When the committee of scientific men 

 who had been charged with the organization 

 of the Anthropological Exposition connected 

 with the Paris World's Fair called on M. 

 Krantz, the Director-General, to obtain his 

 approval of the plan, his reply was : "Gen- 

 tlemen, I must confess that I have never 

 heard anything but evil about you. This 

 has satisfied me that your work is of value ; 

 this has led me to infer that it is useful, and 

 has given me a bias in its favor." 



To test the correctness of the statement 

 which has been made that the leather covers 

 of books in libraries are injured by the com- 

 bustion products of coal-gas, Professor Wol- 

 cott Gibbs has examined the books in dif- 

 ferent libraries, in some of which gas is 

 burned, in others not; and his conclusion 

 is that the effects supposed to be attributa- 

 ble to the burned gas are in reality due to 

 other causes. The trouble is more proba- 

 bly in the tanning of the leather than in the 

 action of the gas ; the older kinds of leather 

 used by binders being of poor quality and 

 badly tanned. 



In 1871 a vessel laden with Italian mar- 

 ble was wrecked off Long Island. Speci- 

 mens of this marble, presenting certain very 

 interesting appearances, having been pre- 

 sented to the Peabody Museum of Yale 

 College, they are described in the " Ameri- 

 can Journal of Science " by Professor Ver- 

 rill. The exposed portions of the slabs 

 are, he says, thoroughly penetrated to the 

 depth of one or two inches by the crooked 

 and irregular borings or galleries of the 

 sponge Cliona sulphurca (V.), so as to re- 

 duce it to a complete honeycomb, readily 

 crumbled by the fingers. Beyond these 

 borings the marble is perfectly sound and 

 unaltered. Professor Verrill has long been 

 familiar with the fact that this sponge can 

 destroy the shells of oysters, mussels, etc., 

 but this is the first instance he has noticed 

 of its attacking marble or limestone, for 

 calcareous rocks do not occur along the 

 portions of our coast inhabited by it. Its 

 ability to rapidly destroy such rocks might 

 have a practical bearing in case of subma- 

 rine structures of limestone or similar mate- 

 rial. 



"Blasting gelatine," a new explosive 

 agent, is formed by dissolving collodion cot- 

 ton in nitro-glycerine in the proportion of 

 10 per cent, of the former to 90 per cent, 

 of the latter. The product is a gelatinous, 

 elastic, transparent, pale-yellow substance, 

 having the density of r6 and the consist- 

 ence of a stiflF jelly. "It is in itself," says 



the "Engineering and Mining Journal," 

 " much less easily affected than Kieselguhr 

 dynamite, but it may be made far more in- 

 sensible to mechanical impulse by an admix- 

 ture of 4 to 10 per cent, of camphor. Ex- 

 periments prove that the new explosive 

 possesses weight for weight 25 per cent., 

 and bulk for bulk 40 per cent., more explo- 

 sive power than ordinary dynamite." 



Professor Emerson Reynolds proposes 

 this simple test of the purity of water : 

 Put into a perfectly clean bottle of white 

 glass one half litre of water, and a piece of 

 loaf-sugar the size of a pea. Then set it 

 on a sheet of white paper in a window ex- 

 posed to the sun's rays for eight or ten 

 days. If the water is then turbid it con- 

 tains foreign substances, impurities, proba- 

 bly sewage. 



The Marquis of Tweeddale (Hay), Fel- 

 low of the London Royal Society and Presi- 

 dent of the Zoological Society, who died 

 last December, at the age of fifty-five years, 

 was a distinguished ornithologist, being one 

 of the best authorities on the birds of India 

 and the Eastern Archipelago. He was a 

 voluminous contributor to the "Ibis," the 

 " Proceedings " and the " Transactions " of 

 the Zoological Society, the " Annals of Nat- 

 ural History," and other scientific periodi- 

 cals. 



Sixty years ago a farmer in Monmouth 

 County, New Jersey, planted with locust-trees 

 several acres of untillable land ; the result 

 of that planting, as related in the " Garden- 

 er's Month]}-," is a good lesson in rural 

 economy. Years ago the trees first set out 

 were cut down, but the second growth 

 quickly covered the ground, and last year 

 this second growth was cut. This timber 

 was worked into farm-fence posts, garden- 

 fence posts, and fence-stakes, the whole 

 worth about $2,000 — the cost of cutting be- 

 ing offset by the fuel value of the tops which 

 were unfit for other uses. One grove thirty- 

 seven hundredths of an acre in area 

 yielded 1,400 "five-hole posts," 150 garden- 

 fence posts, and 200 fence-stakes : at this 

 rate the product of an acre would be about 

 $3,000. 



James McNab, Curator of the Botanic 

 Garden at Edinburgh, died in November, 

 aged sixty-eight years. His predecessor in 

 the curatorship was his father, from whom 

 McNab received a thorough botanical train- 

 ing. Deceased was a frequent contributor 

 to horticultural and scientific periodicals. 



Colonel P. W. Norris lately exhibited 

 at Detroit the head and antlers of a huge 

 animal Killed in the Yellowstone National 

 Park. The antlers are webbed, and the 

 animal to which they belong is believed to 

 have been a cross between the elk and the 

 moose. 



