Popular Science Monthly/Volume 5/June 1874/Notes

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NOTES.

Dr. James McNaughton, President of the Albany Medical College, and Professor of the Practice of Medicine, is supposed to be the oldest medical lecturer now in active service. He has delivered fifty-three annual courses of lectures, and, during this half-century of work, has not missed a dozen lectures or been confined to the house a week by sickness. He is seventy-seven years old, and is hale and active.

The white-willow, it is said, has been used very successfully in Iowa for fencing. C. B. Mendenhall, of Marshall County, has about thirteen miles of white-willow fence, of from three to seven years' growth, of which above half will turn cattle. He has also a grove of white-willows, set out about six years ago, which is considered to be worth about $500 per acre.

A Western paper reports that a spaniel, named Curly, performs the duties of mail-carrier between Lake of the Woods, Dakota, and the Minnesota line, twelve miles distant. Letters and papers are placed in a sack and tied about the dog's neck; he is told to go, and never fails to reach his destination. On his arrival, the mail is over-hauled, the dog is treated to a good dinner, and started back again.

Philadelphia possesses a very energetic Zoological Society of about 500 members. Thirty-five acres of ground in Fairmount Park have been assigned to them for a zoological garden, though for the present they will occupy but ten acres. Within the last six months the society has laid vulcanite walks through the garden, built a monkey-house, and made other provision for a large number of beasts and birds from all parts of the world. A small collection has already been made, which will this summer be added to by importations from Africa, Asia, and Australia. There will be a large aquarium, and it is intended to institute courses of popular lectures on Natural History.

At a meeting of the Philadelphia Academy of Sciences, Mr. Meehan exhibited a small Norway spruce, the branches and leaves of which were of a golden tint. He said that, when plants had little food, or lost their fibres in wet soil, and thus could not not make use of food, the yellow tint was generally seen in their leaves. Judging that something analogous must have happened to the spruce, he, on examination, found its roots thickly enveloped by the mycelia of a fungus, which destroyed the young rootlets as fast as they were developed. Only a few trees in his grounds had been attacked two years ago; but during the past two seasons the fungus had spread underground from plant to plant, till now there were over one hundred diseased. He had supposed the fungus to be of the microscopic kind; but in October last the mycelia developed into a brown agaric with a pileus about two inches broad, but the exact species of which he could not determine. He suggested that, as the phenomena in the case of what is known as "peach-yellows" were of the same nature, those who had the opportunity to examine might find the roots attacked by a fungus in the same way.

It is stated in the Cincinnati Gazette that Mr. S. A. Bell, of Plainfield, Ohio, has found under an ancient mound a quantity of fragments of bones of very young children, with the tooth of a rodent animal, which had been used as a neck ornament. These relics were discovered in a large bed of coal and ashes, indicating that the first had covered a space of twenty-five feet in diameter. It is supposed that the children were the victims of some bloody sacrificial rite. The mound under which the relics were buried was of medium size, and its materials had been transported from a considerable distance, and from several different points.

It is universally admitted that asphalt makes a perfect pavement in all respects, except that it is very slippery under certain conditions, that is, when covered with mud. Hence, if an economical method of keeping the surface clean can be devised, this kind of pavement is to be preferred to all others. Impressed with this belief, the London Commissioners of Sewers have directed experiments to be made as to the best mode of cleansing, and the several asphalt companies have united in offering a premium for any improved plan of effecting this purpose.

Analysis of asparagus-shoots, by A. Vogel, shows that the extremities contain no sugar, though the stem, three or four inches below, contains 1.7 to 2 per cent. The explanation is, that the sugar is used up in the formation of cells, which goes on actively in the shoots. The same is the case with potato-shoots.

Absolutely pure iron is said to have been produced by a Russian chemist, by means of the galvanic battery. During the process, a large quantity of hydrogen was disengaged from the ordinary iron used. The pure iron is a silver-white metal, very malleable and ductile, and so soft as to be readily cut with a pair of scissors. It is very different from iron which has hitherto been supposed to be pure. It oxidizes very rapidly, and water is decomposed by it by the rapid absorption of oxygen.

It is proposed to apply the sand-blast to the quarrying of slate, either for slabs or roofing-slates, thus preventing much of the waste inevitable under the present imperfect methods of quarrying. As this waste frequently amounts in weight to as much as nine times the weight of the marketable article produced, it will be seen that there is a wide margin for the profitable use of this invention. The process is also applicable to quarrying stone, and for cutting hard rocks in railroad tunneling.

The "quick-signal railroad lantern" is a very useful contrivance, and destined to supersede the common lantern on all railroads. This lantern is furnished with a mechanism whereby in the fraction of a second a white light may be changed to ruby, and vice versa. This is effected by means of a small inverted cup of ruby glass which surrounds the flame, having of course an opening above for the escape of smoke. The cup may be depressed beneath the flame, and then the lantern gives a white light; or it may inclose the flame, and then the light is red.

Harness and other articles of leather which are injuriously acted upon by the ammoniacal exhalations common in stables may, according to Prof. Artus, be thoroughly and effectually protected by the addition of a little glycerine to the oil or blacking with which their surfaces are treated.

Iron is not volatile, except at very high temperatures, like gold and platinum. Dr. Eisner, director of the Berlin Porcelain Works, has tried the experiment of subjecting a small piece of iron, in an unglazed crucible, to a long-continued exposure to a temperature of over 3,000 Cent., when he was distictly enabled to recognize minute needles of crystallized iron on the cover of the crucible, the result of vaporization.

Cut flowers may be kept fresh for a fortnight, it is said, by dissolving sal-ammoniac or chlorhydrate of ammonia with the water in which the stems are put, in the proportion of about 75 grains per quart of water. The experiment is one which can be easily made.