SCIENCE NOTES.

Otago Witness, Issue 2236, 7 January 1897, Page 48

SCIENCE NOTES.

• . • A few year* ago a noted scientist made a series of experiments with insects to determine their muscular force. He found that a cookchafer could draw 14 times its own weight and a bee 20 times. From this he argued that, weight for weight, a cockohafer was 21 times stronger than a horse and a boe 30 times. Boon after another scientist, noticing the terrible snap of a crocodile's jaw, proceeded to experiment with one of these oreatures. Having securely fastened the lower jaw and feet to a table, he attached a dynamometer to the cord which secured the i»PP« jaw to a baam above. The crocodile,

being angered by a slighfc<eleclric shock, was induced to snap i( s teeth. The dynamometer showed tbafc the beast, which weighed 1201b, made an effort of 30Slbin closing its massive jawe. • . • Officials of the Erie railroad are considering the advisability of establishing the übo of horseless carriages in connection with railroad passenger business. The company proposes to arrange matters ao tbat a passenger can telephone the cifcy ticket; office, notifying the agent that he wishes to take the train, and a horseless carriage will carry him to the station from his home at the proper time. The maintenance of the vehicles would be practically nothing, and the company's service would be greatly improved. The scheme will probably be experimented wifch in New York first. •.• The farmers of North Holland, ssaby b a correspondent of the G?.s World, have come into possession of a very interesting source of lighting. About 40 years ago borings for water in the poldeis around the Haarlem lake, at farms below the level of the surrounding se», brought up inflammable gas; but, as this gave no light, it was neglected. Now, however, this gas is being systematically bored for, and it comes up mixed with Bweet water, making this water effervesce. The effervescing water is brought under a gas holder, and the gas isliberated while the water flowa on. About six cubic feet per hour are thus collected from each boring, and the singular result is that many outlying farms away on the polders of North Holland, below sea level, are brightly lit up at night by incandescent burners. . • Two physicians connected with a hospital at Ogdensburg, N.Y., suspect that certain forms of insanity arc dne to a particular microbe, says the New York Tribune. Drs P.M. Wise and Warren L. Bibcock are the men. They received a bint of this theory from a foreign scientist, Dr GalceraD, of Barcelona, Spain ; but they have been experimenting with patients in their own hospital, and in consequence are inclined to adopt the opinions just mentioned. They took a person who was suffering from acui,9 delirium, inserted a auction needle into the membranes betide the spinal cord, down near the waist, and extracted a little of the moisture which is usually found there. Theso membranes, it should be explained, are continuations of muixkbranes around the brain, and the fluid in tha two placeß is considered identical. That which was extracted by the needle was supposed to contain bactoria. At any rate, rabbits which were inoculated therewith became sick, although it is not alleged that they were insane. It does not appear distinctly either that Drs Wise and Babcock have been able to find and describe any particular form of microbe as belonging to delirium. Their case is nol; yet proved. Much less have they shown that acute mania can be cured by inoculation with modified germs.— Scientific American. • . • The late Dr Brown Goode made the following comparison in a report of the United States National Museum : " There is not a department of the British Government to which a citizen has a right to apply for information upon a scientific question. This seems hard to believe, for I cannot think of any scientific subject regarding which a letter, if addressed to the scientific bureaus in Washington, would not receive a full and practical reply. It is estimated that not less than 20,000 such letters are received each year. The Smithsonian Institution and j National Mugoum alone receive about 6000, ! and the proportion of these from tha new i States and territories, which have not yet developed institutions of learning of thoir i own, is the largest. An intelligent question from a farmer of the frontier receives as much attention as a communication from a royal academy of sciences, and often takes more time for the preparation of the reply." ; « ' The jDWIQMSd joll of thuftd«r is readilj '

explained by comparison with a volley fired along a line of troops. Suppose troops to be drawn up in a line in such numbers as to extend for a mile, and ordered, by a signal that all could see, to fire at ones. One standing at the end of the line would hear the report of the musket nearest him instantly. He would hear the others succeisively. Thus a report 550 ft away would come to him in half a second, and he would not hear the last report for five or six seconds after the gun had been fired. This would produce a sort of roll, which would gradually increase in intensity. Flashes of lightning may be considered as representing three lines of troops along which tbe explosions oconr at tbe same time. Consider tbe variety of distance and position of the listener, and we account for the variety of sound in thunder. In mountainous regions the rolling is augmented by reverberations or eoboes. | '.'Files and rasps used for working tin : and lead can be cleaned and sharpened in the following manner : — Dip the" file for a few seconds into concentrated nitric acid until reddish brown vapours commence to ascend lively, then rinse in water, rub with a sharp brush and imbed the file in sawdust or coaldust, or dry it quickly for immediate use, A file clogged up by iron filings should i be dipped into a watery solution of copper I vitriol, by which the filings are dissolved and | copper preoipltated in the form of a slimy sediment, while the body of the file is attacked but little. Afterwards rinse the I file in water, brush off, dip into nitric acid, i and conclude treatment as above. Files dulled by zinc filings are given a bath in diluted sulphuric acid, otherwise the? are subjected to the same treatment. Clean all files used for working oopper by means of nitric acid, but repeat the procosa several times, because the first time much copper 3s ' precipitated that adheres tenaciously to the body of the file. Files used for working wood are first pub into hot concentrated sulphuric acid, riDsed, brnshod, then clipped into lye of potash, rinsed and brushed again, and finally dried. Dryisg can be accomplished best and quickest by pouring alcohol over the file and burning ifc off.-^American Manufacturer. •.' Scientific agriculture is largely bated on our knowledge of tha selective power of the Vegetable cells to appropriate in tha proportions demanded by the economy of the particular species the sales and bases present in the soil, but that this selective affinity is unattended by a corresponding power of rejection is seen in the rapidity with which any plant may bB killed by a large dose of crude organic fluids, as urine or milk, or solutions of albuminoids, urea or carbohydrates, which they are incapable of assimilating, and which must be "mineralised" by bacterial agency in order to be available as food for plants. The experiments of Dr K. B. Lehmann reported in the Archiv fur Hygiene, xxviii, Bind. 1 H., are of considerable interest as regards the presence of copper in the soil and its absorption by the vegetation. His observations were made in and around some disused copper mines worked near the surface on a rocky hillside, where the green and blue discolouration of the stones afforded palpable evidence of the presence of copper in soluble forms. The plants growing in each portion of the locality yielded very different prfeportions of copper, varying not only with that in tha soil but with the particular species, and the several structures or tissues differed greatly in their power of absorption or storage of the metal. Dr Lshmann took away with bim a two-yearold hen and three ogga ; tbe muscles of the fowl were found to contain copper in the proportions of 2-4 milligrammes, and the liver 3.12, while in the feathers it reached 10 milligrammes per kilogramme. The parallelism between these and the bark of tree?, alike inert and sclerosed tissues, is noteworthy. Copper was present also in the egsis — I'BB milligramme in the she)], 823 milligrammes in the white, and 14 milligramme in the yolk per kilogramme, while in others bought in Wutzburg ifc was wholly abßent or there were but doubtful traces in the yolk. — Lancet.