572 



THE POPULAR SCIENCE MONTHLY. 



British Gold-Mines. — The existence of 

 gold in the British Islands, in quantities per- 

 haps sufficient to pay for modest mining, 

 seems to be established, thereby justifying 

 Strabo's inclusion of the precious metals as 

 among their products. In Wales, gold is 

 found in Carmarthenshire and Merioneth- 

 shire. At Gogafan, in the former county, are 

 to be seen traces of extensive ancient (prob- 

 ably Roman) workings. At the Viga Cloga 

 Mine, an average annual return of £2,500 

 was realized from 1860 to 186*7, since when 

 the yield has declined. In this mine the 

 vein appears to have been more productive 

 as the working was extended to a greater 

 depth, contrary to what is generally believed 

 about gold-mines. From the Cambrian 

 Mine, 300 ounces, and from the Prince of 

 Wales's Mine, from 300 to 400 ounces of 

 gold have been extracted to the ton of ore. 

 Gold-fields wei-e worked in Ireland at the 

 close of the last century, but oi)erations 

 wore stopped in 1802 because the cost ex- 

 ceeded the profit. The attempt was re- 

 newed in 1840, but given up again on 

 account of disputes. The principal mining 

 sites were Ballin Valley, Ballintemple, and 

 Killahurler. Gold-fields lie in Lanarkshire 

 and Sutherlandshirc in Scotland. They 

 were worked with considerable profit in the 

 days of the Jameses. The gold-field of 

 southeast Sutherlandshirc covers an area of 

 thirty miles by twenty. The occurrence of 

 gold in England is rather a matter of specu- 

 lation ; but it exists, and can be found and 

 obtained. Mineral in north Cornwall has 

 assayed eleven ounces to the ton. Mr. J. S. 

 Farrer thinks that the reason no gold-mines 

 are at present being worked in the United 

 Kingdom may he " far more in the state of 

 the law than in that of the ground." 



Children's Pnnishments.— Something can 

 be said in favor of most of the forms of cor- 

 rection — the rod, strap, tasks, confinement, 

 restriction to plain food, and many others — 

 which have been more or less employed in the 

 school and the family. But there is one which 

 on no account should be employed. Boxing 

 or pulling the ears, or, indeed, striking any 

 part of the head, is most injudicious. Not 

 every form of corporal punishment is so 

 objectionable, but in applying it judgment 

 should be employed. Thus, if a chastise- 



ment suitable for a robust child is given to a 

 nervous or feeble one, it will be doubly felt, 

 and will be out of proportion to the offense. 

 Moral means of correction may be the most 

 suitable for sensitive children, and, in the 

 case of school tasks, may possess a certain 

 educational value. There is, however, an 

 important objection to such as imply con- 

 finement indoors, especially in cases where 

 the culprit is some poorly nourished young- 

 ster to whom fresh air is a luxury, or in 

 any case where the punishment is frequently 

 repeated. 



Searching for the Canals of Mars. — In 



his report at the American Association on 

 the aspect of Mars, as observed at the Na- 

 tional Observatory, Washington, Prof. A. 

 Hall said that while observing satellites 

 in April, attempts w^ere made on several 

 nights to see the canals, but without success, 

 and then it was determined to make the 

 trial in twilight, when the observers could 

 see more in detail on the surface of the 

 planet. But nothing like the regular canals 

 drawn by European observers could be seen, 

 although the usual reddish and dark spots 

 and markings were visible nearly every 

 night. 



Japanese Mirrors. — The peculiar prop- 

 erty of the Japanese " magic mirrors,-' some 

 of which reflect the figures carved or 

 stamped on their hacks, was explained by 

 Prof. Mendenhall, at the American Associa- 

 tion. It has been known to the Japanese 

 for a thousand years, but did not receive 

 scientific attention till a few years ago, when 

 a Frenchman studied out the reason of it. 

 The mirrors are round metal disks with 

 short handles covered with bamboo and 

 curiously carved backs. The peculiar thing 

 about them is that, when a ray of light is 

 reflected from their surface upon a screen, 

 instead of a mere blotch of light there ap- 

 pears a reflection of the figures upon the 

 back of the metal. How this is accom- 

 plished Prof. Mendenhall explained on the 

 principle of the divergence of rays of light 

 fx-om a convex surface. It has been dis- 

 covered that the polished surfaces of some 

 of the mirrors are slightly convex. In ad- 

 dition to this, the smooth surface is really 

 irregular, though the irregularity can not be 



