512 



THE POPULAR SCIENCE MONTHLY. 



propagation of worms which destroy the 

 roots of the vine. He would thus do away not 

 alone with the vines, but also with the van- 

 ity of the French, for, says the Saturday 

 Hevieio, " it is impossible to conceive that 

 vanity could remain in a nation whose sal- 

 vation had been effected by so humble and 

 earthy an instrument." 



In many places in England they have 

 for several years been using a safety-valve 

 for steam-boilers that appears to be an ab- 

 solute safeguard against explosions from 

 low water. The valve is entirely within 

 the boiler, and so rigged that when the water 

 falls to a certain point the valve opens and 

 a jet of steam is discharged upon the fires, 

 the valve closing again when the water in 

 the boiler is restored to its proper level. 

 Being beyond reach, the valve cannot be 

 tampered with, and, having its working-parts 

 above high-water level in the boiler, it is 

 not liable to get out of order from corrosion. 

 Where these valves have been used, they 

 have proved to be perfectly efiScacious as a 

 complete safeguard against explosion and 

 collapse ; and they are most highly spoken 

 of, not only by steam-users, but also by 

 inspecting engineers of boiler-insurance 

 associations. 



The greater the specific gravity of a 

 gallon of oil, the greater will be the amount 

 of light obtainable from it; or, in other 

 words, a gallon of heavy oil, burning with a 

 flame of given size and luminosity, will last 

 longer than a gallon of lighter oil, burning 

 in the same manner. The light oil is more 

 volatile, passes off into vapor, and is con- 

 sumed more rapidly; thus the most dan- 

 gerous oils are the least economical. 



In the Jardin d' Acclimatation at Stras- 

 bourg is a machine contrived for the fatten- 

 ing of fowls. The fowls are placed in a 

 kind of dove-cot ranged in five different 

 stages, each stage holding forty-two birds, 

 which are separated from each other by 

 vertical partitions, and which are so secured 

 that their head and wings alone remain free. 

 The " feeder " stands in front, and, taking 

 the head of the bird in his left hand, forcibly 

 introduces down its neck a quill which is in 

 communication, by means of a hose of In- 

 dia-rubber, with a kind of reservoir full of 

 the food beneath. The operator presses 

 with his food upon this novel species of 

 bellows, and a dial placed opposite to him 

 registers the exact amount of food to a 

 fraction of a cubic inch. The amount of 

 this singular dose differs according to the 

 age and species of the patient, as well as to 

 the degree in which it is desired he should 

 be fattened. In eighteen days a fowl can be 

 brought to the point of fatness desired, and 

 in certain very favorable cases the weight 

 has actually been doubled in that time. 



The Annual Meeting of the American 

 Association for the Advancement of Science, 

 which it was expected would be held in San 

 Francisco, is to take place at Dubuque, Iowa, 

 commencing on Wednesday, August 21st. 



A remarkable instance of tolerance by 

 the human system of the excessive use of 

 tobacco is afforded in the case of M. Klaes, 

 of Rotterdam. This gentleman, who was 

 known as the "King of Smokers," has just 

 died, in his eightieth year, and is said to 

 have consumed during his long life more 

 than four tons of tobacco. The ruling pas- 

 sion was apparent in the will of the deceased, 

 and in his eccentric request that his oak 

 coffin might be lined with the cedar of his 

 old cigar-boxes, and that a box of French 

 caporal and a packet of old Dutch tobacco 

 might be placed at his foot, and by the side 

 of his body his favorite pipe, together with 

 matches, flint and steel, and tinder. Lancet. 



Dip the hand into a finger-glass until 

 the water in it is warmed one degree. An 

 amount of energy is withdrawn from that 

 hand sufficient to project that water to a 

 height of 772, or, if the degree be centi- 

 grade, to a height of 1,390 feet above the 

 earth's surface three times the height 

 of St. Paul's. Tyndall. 



Caoutchouc is easily joined and made 

 as strong as an original fabric, by softening 

 it before a fire and laying the edges care- 

 fully together, without dust, dirt, or moisture 

 between. The edges so joined must be 

 freshly cut. Tubing can be made by join- 

 ing the edges of a sheet of India-rubber 

 round a glass cylinder, which has previously 

 been covered with paper. After the glass 

 is withdrawn the paper is easily removed. 

 Sift flour or ashes through the tube to pre- 

 vent the sides from adhering from accidental 

 contact. 



In a note to the Paris Academy of Sci- 

 ences, on the influence which changes in 

 barometric pressure exert upon the phe- 

 nomena of life, M. Bent describes the effects 

 produced by exposing small animals to vari- 

 ous degrees of atmospheric pressure. He 

 has found that, up to a pressure of two at- 

 mospheres, sparrows die when the air in the 

 receiver contains 25 per cent, of carbonic 

 acid, but that, above this limit, and below a 

 pressure of ten inches, this law does not ap- 

 ply- 



At the recent meeting of the French 

 Departmental Learned Societies, held at the 

 Sorbonne, gold medals were awarded to M. 

 Grandidier, for his geographical, geological, 

 meteorological, and botanical works, in par- 

 ticular of the island of Madagascar ; and to 

 M. Houzeau for his discoveries respecting 

 ozone, which he is enabled to produce in 

 large quantities. 



