NOTES. 



255 



Aa Aroiy of Caterpillars. A writer in 

 the Gardener's Monthly gives some interest- 

 ing particulars concerning the habits of the 

 caterpillars, which last spring visited the 

 region about Memphis in such unheard-of 

 numbers. They were so numerous, that 

 several trains of cars coming into the city 

 were stopped on each of the two roads, the 

 masses covering the rails for hundreds of 

 yards in a body, compelling the brakemen 

 to get down and sweep them off before the 

 driving-wheels could get sufficient hold to 

 pass over the obstruction. They lived on 

 the young leaves of both forest and fruit 

 trees the oak, quince, apple, and plum, 

 being their favorite food. "Whole orchards 

 were denuded of foliage, and great lanes of 

 bare trees marked their track through the 

 forests. They are characterized by one 

 remarkable peculiarity. Unless prowling 

 through thick grass, or when about half 

 grown, descending by the long web which 

 each spins, from a tall rough forest-tree, 

 they are always arranged in military style ; 

 . and travel, also, in long, straight lines, sev- 

 eral abreast. 



lasect-Life ia a Coal-Minc. A coal-pit 

 in England having become infested with 

 large-winged insects, which caused the 

 workmen considerable annoyance, by flit- 

 ting around their lamps and often ex- 

 tinguishing them, a search was made to 

 discover the source from which they came. 

 The wooden props supporting the workings 

 were found to be pierced in several places, 

 as though by gimlets, and in the holes were 

 found a number of moth-like insects. The 

 wood had come from abroad, and had been 

 in the pit some four years before the insects 

 began to make their appearance. 



Au Fapatcntable Pavemeat. A writer 

 in the Journal of the Society of Arts advo- 

 cates the adoption of a kind of wooden 

 pavement for the .streets of London, which 

 in point of wear he believes to be superior 

 to all other varieties of wooden pavement, 

 and with the additional advantage that it 

 cannot be made the subject of a patent. 

 He says : " Xow, the only wood pavement 

 fit to stand London traffic, and entailin"- 

 the smallest cost, could not be patented by 

 the most astute lawyer. Instead of fashion- 



ing the blocks into patent dice, hexagons, 

 polygons, or dove-tailed complications in 

 any form, we have only to slice barked trees 

 of any size or quality into cylindrical slices 

 about thirteen inches in thickness, and put 

 the largest size down first into a good 

 rammed foundation, and then the smaller 

 sizes, until the remaining interstices may be 

 filled up with what may be called pegs, the 

 proper ramming of which will render the 

 whole one solid mass of timber, while the 

 economy of wood is so great that not a 

 chip will be wasted. The surface will pre- 

 sent end-grain only, and with the different 

 sorts and sizes will afford a much better 

 foothold than granite blocks." 



Gold la Sea-Water. In a series of re- 

 searches on the composition of sea-water, a 

 chemist named Sonstadt has been able to 

 make out the presence of gold as one of its 

 constituents. It appears to be completely 

 dissolved, and is held in solution by the 

 action of iodate of calcium, which, as shown 

 by the same chemist, sea-water also con- 

 tains. He demonstrates the presence of 

 gold by three separate and entirely different 

 methods, and estimates the proportion to be 

 less than one grain per ton of water. 



NOTES. 



Non-inflammable Fabrics. Cotton or 

 linen goods may be rendered non-inflamma- 

 ble by being dipped in a solution of equal 

 parts of acetate of lime and chloride of cal- 

 cium dissolved in twice their weight of wa- 

 ter. 



Taper Lamp-Shades. Dr. Minis men- 

 tions two cases in Jena and one in Frank- 

 fort where persons using green glazed paper 

 lamp-shades were poisoned by the arsenic 

 of the coloring matter. The heat of the 

 lamp volatilized the arsenic, and rendered 

 the small quantity present very dangerous. 



Progress of Chemistry. One by one 

 the organic products are being copied in the 

 laboratory. The last triumph in this direc- 

 tion which has come to our notice is the 

 production of glycerine by Friedel and Silva. 

 If the vapor of fusel-oil be passed through 

 a red-hot tube, propylen is formed, which 

 readily combines with chlorine, and from 

 this chloride of propylen glycerine is pro- 

 duced by a process in which no glycerine is 

 employed. As glycerine is the base of all 

 true fats, this is an important step in the 

 direction of oil-making. 



