Sept. 5, 1884.] 



♦ KNOWLEDGE ♦ 



205 



i^flisirfllanra. 



Mineral wool is, says the Scientific American, used for a packing 

 to deaden the sound between floors in buildings, and being incom- 

 bustible it is now pretty generally nsed between the floors and 

 ceilings in new houses. Mineral wool is obtained from the slag 

 from blast furnaces, and is produced by throwing a jet of steam 

 against the stream of slag as it flows from the furnace. 



The Blenheim Picti:hes.— " Atlas," in the World, gives some 

 jiarticnlars in regard to the sale of the Duke of Marlborough's 

 pictures. The agent in the matter is Mr. Davis, of lt7, New Bond- 

 street, London. So far he has been most successful in his sales. 

 For four pictures Mr. Davis has obtained for the Duke £'140,000, 

 one of the number being the famous Raphael, for which the 

 (Government has undertaken to pay £70,000. 



Wide Reach of a Tidal Wave. — A correspondent in the Fiji 

 Islands writes that a notable tidal wave reached thci'o on 

 October 6 last, the date of the great tidal wave, 25 feet high, 

 and the eruption of Mount St. Augustin, in Alaska. The tidal 

 wave in Alaska occurred at 8.25 a.m., and that at the Fiji Islands, 

 about 4,500 miles to the south-west; at 11.15 a.m. At the latter 

 place there were three successive waves, with intervals of ten 

 minutes, which, at the ordinary period of low water, reached nearly 

 to the high-water mark. The occurrence of this disturbance of the 

 sea a few hours later on the same day as the eruption of Mount St. 

 Augustin, and the formation of a new island in its vicinity, suggest 

 that the tidal wave at both places proceeded from the same cause. 



In the Intehests of Science. — A contemporary is informed 

 that the Warsaw Courier has published a letter from a subscriber 

 in which the wi-iter offers himself as a stibjcct to be experimented 

 upon in reference to clolera. " I am unmarried," says he, " I have 

 no ties of any kind, ami no plans for the future. I tberefore wish 

 to be of use to humanity by undergoing any experiments which 

 have not yet been tried upon human beings. I seek no reward, but 

 should require to be paid my travelling expenses to wherever I 

 might have to go to be experimented upon, and those of my return 

 journey to Warsaw should I be spared to perform it. I may add 

 that I am twenty-four years of age and in good health." The 

 writer says that communicatioas in answer to this may be sent to 

 "Z. A. K.," care of K. Tsibulski, china and glass dealer, Theatre- 

 place, Warsaw. 



Coral-Fishing. — Coral-Sshin^ is largely followed in Algeria, 

 40,000 to 45,000 pounds of coral, valued at about £38,000, "being 

 the yearly production ; Li Ca'le is the centre of this industry, and 

 there are employed annually ICO boats and 1,300 men. The coral 

 is obtained by means of a wooden apparatus in the shape of a cross, 

 having in its centre a leaden slug or stone for ballatt. Nets, the 

 meshes of which are loose, are hung on the bars of the cross and 

 dragged at the bottom of the sea, among the nooks and crevices of 

 the rocks. These nets, winding about the coraline plant, break up 

 or tear off its branches, which adhere to the meshes. The appa- 

 ratus is drawn up by the fisherman whenever he thinks it suffi- 

 ciently laden. There is also a net which is jirovided with large iron 

 nails, having thus greater force to break the coral, but this appa- 

 ratus is forbidden to be used. — Scientific American. 



The Abyssinian tube-well for the entire supply of the town of 

 Hertford has been completed by the contractors, Messrs. Le Grand 

 >fc SutclifEe, with most satisfactory results. The size of the tube 

 well is 7i in., and at 81 ft. the chalk springs are so abundant that 

 the yield is over 100 gallons per minute, or about 150,000 gallons 

 per day. The pnmping, when necessary, can be continued night 

 and day with a very small amount of attention, as the motor is a 

 powerful water-wheel worked by the river Lea. This well affords 

 a further illustration of the fact stated by Mr. Robert Sutcliffe at 

 the recent Water Supply Conference held at the Health Exhibi- 

 tion, that it frequently happens there is abundance of good water 

 t3 be found on the banks of a river that is no longer itself fit to 

 sapply water for dietetic purposes. The total saving of the expense 

 of filtration is also a very important item, which might, to some 

 extent, recompense the London water companies for the expense of 

 obtaining their supplies from sources that need no outlay on this 

 head. The total cost of the tube-well, including cast-iron connec- 

 tions to pump, was under £150, so that the town supplies on this 

 system cannot be considered extravagant. 



Efficacy of Vaccination. — In his rei)ort of the working of the 

 Homerton Small-pox Hospital, Dr. Gayton supplies us with the 

 most recent, as well as most cogent, proof of the marvellous effi- 

 cacy of vaccination as a prophylactic, and of the utter ignorance 

 and crass stupidity of the peo]>le who are induced by paid agitators 

 to lend their names and their uneducated minds to the contest 

 against vaccination. From .lauuai'y 1 to March 7, 1883. during 

 which time the small - pox patients were treated in the Fever 

 Hospital, 02 cases were admitted ; of these, 43 were 



vaccinated, of whom 3 died, or at the rate of 70 per 

 cent. ; 12 were doubtfully vaccinated, of whom 3 also died, or 

 at the rate of 25 per cent. ; and 7 wore unvaccinated, of 

 whom again 3 died, or at the rate of 4285 per cent. From March 

 7 to the end of the year, 325 patients were admitted — viz., 237 

 vaccinated, 30 doubtful, and 58 unvaccinated. Amongst these 17, 

 5, and 25 deaths respectively occurred, or at the respective rates of 

 702, lG-6, and 431. It seems, therefore, that the unhappy child 

 who, by the influence of these foolish people, has been deprived of 

 the benefit of vaccination, runs a risk of death from small-pox more 

 than six times greater than the child who has undergone the harm- 

 less operation necessary to preserve him against that disease. — The 

 Medical Press. 



The AxTiquiTY of Merccry. — A recent writer in the North China 

 Herald discusses the part played by mercury in the alchemy and 

 materia medica of the Chinese. Cinnabar was known to them in 

 the seventh century before the Christian era, and its occurrence on 

 the surface of the earth was said to indicate gold beneath. Their 

 views on the transformation of metals into ores and ores into 

 metals by heat and other means took the form of a chemical 

 doctrine about a century before Christ, and there is now no reason- 

 able doubt that the Arabian Geber and others (as stated by Dr. 

 Gladstone in his inaugural address to the Chemical Society) derived 

 their ideas on the transmutation of metals into gold and the 

 belief in immunity from death by the use of the philosopher's 

 stone from China. Among all the metals with which the alchemist 

 worked, mercury was pre-eminent, and this is stated to he really 

 the philosopher's stone, of which Geber, Kalid, and others spoke 

 in the times of the e;irly Caliphs. In China it was employed ex- 

 cessively as a medicine. On nights when dew was falUng a suffi- 

 cient amount was collected to mix with the powder of cinnabar, 

 and this was taken habitually till it led to serious disturbance of 

 the I o lily functions. In the ninth century an emperor, and in the 

 tenth a prime minister, died from over doses of mercury. Chinese 

 medical books say it takes two hundred years to produce cinnabar ; 

 in three hundred years it becomes lead ; in two hundred years 

 more it becomes silver, and then by obtaining a transforming sub- 

 stance called " vapour of harmony " it becomes gold. This doctrine 

 of the transformation of mercury into other metals is 2,000 years 

 old in China. The Chinese hold that it not only prolongs life, but 

 expels bad vapours, poison, and the gloom of an uneasy mind. 



" lict Knowledge grow from more to more." — Alfred Tennyson. 



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AND DIKECTED ENVELOPE BE ENCLOSED. 



DAISIES. 

 [1381] — I never had the slightest desire to exterminate daisies 

 anywhere, and I have not the remotest idea how anybody seized 

 with such an unnatural longing could proceed to gratify his or 

 her wicked and destructive tastes. Perhaps the easiest way out of 

 the difficulty would be for the " Disconsolate Female " to aim at 

 acquiring a more reasonable liking for beautiful natm*al objects, 

 and to correct the mistaken feeling which prefers an artificially 

 smooth lawn to the graceful variety of self-sown herbage. 



Grant Allen. 



FALSE PERSPECTIVE. 



[1382] — It was a grave omission in the elementary works on 

 Perspective not to have pointed out to T. E. (R.) Jones that the 

 appearance of his "Plane of the Picture," and of the lines drawn 



