POPULAR MISCELLANY. 



429 



gun could be fired, and which would seldom 

 be reached by the sound of its discharge. 

 A kind of cartridge of tonite has been made, 

 to be sent high up into the air, explode 

 there, and scatter a shower of brilliant 

 stars, and has been adopted for the pur- 

 pose of making signals on many vessels. 

 Mr. Price-Edwards does not express a high 

 opinion of whistles ; but one of Mr. Courte- 

 nay's automatic buoy-whistles has been used 

 off the Goodwin Sands with success, and 

 two others are to be placed off the English 

 coast. The palm of superiority in all re- 

 spects, as a signal, is accorded to the Ameri- 

 can siren. Among the improvements that 

 have been made in it are one for increasing 

 the suddenness and intensity of the sound, 

 adaptations for use on ships and steamers, 

 and the double siren, in which two notes are 

 produced simultaneously, the power of the 

 instrument is more than doubled, and a 

 characteristic feature is given to the sound. 



The Mekarski Air-Engine. The Me- 



karski air-engine, which has been employed 

 satisfactorily for several months on the 

 tramways of Nantes, France, is being intro- 

 duced into England by the Compressed Air- 

 Engines Company. Both engines combined 

 with the car and simple traction-engines 

 are used at Nantes. In the combined cars 

 and engines, ten cylindrical steel reservoirs 

 for the compressed air are placed beneath 

 the floor, seven of which are united into 

 one system, called the " battery," and the re- 

 maining three are united into a second sys- 

 tem called the " reserve." Both the bat- 

 tery and the reserve are charged at the prin- 

 cipal station with air compressed to thii'ty 

 atmospheres. The cylinders are placed hori- 

 zontally in front of the driving-wheels, and 

 are five and three eighths inches in diam- 

 eter, by ten and a quarter inches stroke. In 

 front of the car, and on the driver's plat- 

 form, is a small reservoir, which is charged 

 with water, for about two thirds of its ca- 

 pacity, at a temperature of 320. The air, 

 in passing from the battery or from the 

 reserve to the engines, traverses the water 

 in this reservoir, and thus becomes heated 

 before reaching the cylinders. After doing 

 its work in the cylinders, it passes into a 

 box, from which it escapes into the air. 

 Under this arrangement, which is peculiar 



to the Mekarski engine, a smaller quantity 

 of air is needed, and the danger of ice 

 forming in the exhaust passages of the cyl- 

 inder is obviated. A regxxlating valve on 

 the top of the hot-water reservoir serves to 

 keep the air from the reservoirs at a uni- 

 form pressure, whatever may be the varia- 

 tions in the demand by the engines. The 

 combined car, when ready for work, weighs 

 six tons. The traction-engines draw two 

 cars each. The charge of air carried is 

 enough for the whole " round trip." 



Stone-Age CiYilization in New Gninea. 



The Papuans of the Maclay coast, New 

 Guinea, afford a fine and instructive speci- 

 men of a living race still in the stone age. 

 The implements on which they have ex- 

 pended their artistic skill come under the 

 two categories of fragments of flint, shells, 

 and bones, and chipped stones in the form 

 of axes. The ornaments upon them are 

 classified by Mr. J. C. Galton, in a notice of 

 M. Maclay's observations, into ornaments 

 made solely for a decorative purpose, orna- 

 ments and drawings demonstrating the first 

 beginning of the figurative or ideal style of 

 writing, and ornaments, sketches, and carv- 

 ings, which stand in close relation to the su- 

 perstitions and dark religious ideas of the 

 Papuans. The salient character of the orna- 

 ments is that they are generally rectilin- 

 ear, and this is because the bamboo and 

 reed, on which ornamentation was first at- 

 tempted, do not conveniently admit of any 

 other style of drawing. The style thus fixed 

 on wood was readily transferred to other 

 substances on which decoration was at- 

 tempted. That the want of variety in sub- 

 jects of decoration does not proceed from 

 lack of inventive power and skill is shown 

 by the fact that as soon as some of the 

 men got improved tools, such as bits of 

 glass bottles, they introduced refinements 

 and variations into their wood ornamenta- 

 tion. The Papuans have been supposed to 

 be destitute of any art of writing, but M. 

 Maclay believes that he has found evidence 

 of the use by them of an ideograph in a 

 very rude form. He observed rude figures 

 painted in different places in various com- 

 binations, the purpose of which puzzled him 

 for a long time, till it was revealed at a 

 feast which was held on the occasion of the 



