NOTES AND MEMORANDA. REFRIGERATING SALTS.-Herr F. Rüdorff has a paper in Poggend. Ann. comparing the refrigerating effect of various salts in solution. The two most remarkable seem to be the sulpho-cyanides of ammonium and potassium; 133 parts of the former added to 100 of water reduced the temperature of the liquid from 12·2° C. to -18° C., while 150 parts of the latter in 100 of water, reduced it from 10.8° C. to -23-7° C. or 34.5°. To produce a maximum of effect, quantities of from 250 to 500 grammes of the salt employed should be used, in a thin glass vessel surrounded by loose cotton. The salts should be an impalpable powder, and well stirred with the thermometer. A little more of the salt should be used than would suffice to saturate the water. The minimum temperature may be obtained in less than a minute. THE AGE OF WRITINGS IN COMMON INK.-M. F. Carré has communicated to the French Academy remarks on an approximate determination of the age of writing made with ink having like those in common use an iron base. He says, that writing, eight or ten years old may be copied with an ordinary press, if the copying paper is moistened with water to which one-twelfth of hydrochloric acid has been added. In this case the copying is almost as easy, as when it is done upon fresh writing in the usual way. The facility of the copying process diminishes with time, and a writing thirty years old did not give a legible copy, while one dating 1787, scarcely yielded a perceptible trace. When writings are washed with, or soaked in dilute hydrochloric acid of the strength mentioned, an inverse action is noticed. Those made from a few months to ten years ago disappear after an immersion of from a few hours to a few days, while a writing thirty years old could be read after fifteen days maceration. When copies are made with acidulated paper, they should be held over a dish containing liquid ammonia for a few seconds to neutralize the acid. THE COURAGE OF THE WEASEL.-Frequent mention has been made of the boldness of the weasel, which is curiously illustrated by the following fact. The editor was lately walking in his garden in Sussex with two ladies and a gentleman, when a small animal was seen busy on the lawn a few yards off. The party stood still to look at it, and the creature trotted towards them. It made a slight attempt to pass them by dodging behind a bush, but not succeeding, boldly approached, and allowed itself to be taken up in a pocket-handkerchief without a struggle. After being carried about for ten minutes and shown to several people, it was replaced on the grass, but instead of running away, it made a curious squeaking noise, and opened its mouth as if to bite. Stroking it with the handkerchief caused it to renew its bold demonstrations, but on being left alone it ran slowly through an evergreen harbour towards a bank in which it is supposed to live. It did not seem at all afraid, or much annoyed at being handled, and only resented it by diffusing its nasty and characteristic odour. This incident happened in broad daylight. THE APOMECOMETER.-In our April number we gave an account of an ingenious modification of the sextant to form a small pocket instrument for measuring heights, devised by Mr. N. J. Heineken, of Sidmouth. We have since received from that gentleman a letter stating, that his attention has been called to Millar's apomecometer made by Mr. Stanley, of Great Turnstile, very similar to his own. Mr. Heineken's last instrument is only a variation from one he made in December 1868, and was used by him and a friend (Dr. Radford), in January 1869. Mr. Millar and Mr. Heineken, working independently, seem to have devised a very similar modification of the principle of the sextant. Alimentary substances, regeneration, 388 Ammoniacal salts, manufacturing, 391 Amphinome, seta of, 109 Amphioxus, 326 Anatomy of stentors, 352 Ancient Britons, cannibalism of, 60 Aniline black, manufacture of, 235 Annelida errantia, 161 Annelidan worms, 91, 161, 261, 321, 432 Annular eclipse of the sun, 43 Anthropomorphism, 269 Antidote to phosphorus poisoning, 240 Ants, white, black, and red, 336 Aphrodiseans, 161 Aphrodita aculeata, 104, 162 Aphrodita hystrix, 162 Aphrodita bystrix, foot of, 109 Apomecometer, 466 Application of gas and vapour, 235 Archæologia, 60, 229, 313, 384, 458 Arctic expedition from Sweden, 159 Ariciidæ, 321 Aristarchus and Linné, 190 Artificial stone, composition for, 388 Astronomical notes, 35, 125, 217, 279, 866, Astronomy, progress of, during present Atmosphere in the moon, question of, 257 Blenny, 416 Blocks for surface printing, 462 Blue sky, Tyndall on, 160 Bourgeoisie, power of the, in the fourteenth Blood corpuscles, oviparous vertebrate, Brassington Moor, stone circles at, 347 FABRICS, textile, 67 Falconry in the Middle Ages, 138 Fauna of Malay Archipelago, 222 Fermails or brooches, 200 Ferreting the rabbit in the feudal periods, Feudal lady out of the castle, 11 Feudal period, hunting and hawking in Fiddian's lamp, 80 Fishes of the Holy Land, 409 Fruits, equatorial, 224 Fruits of coriaria, 26 Fuel, utilizing, 316 Fungi, growth of, in chloride of magne- sium, 80 Furnaces, blast, 387 469 HABITS of Ourang-utan, 223 Halley's comet, probable meteors of, 281 Head-dress in Feudal Ages, 198, 202 Heat, solar, as a motive power, 57 Height of glaciers above sea level, 55 Herculaneum, destruction of, 173 Holy Land, fishes of the, 409 Hands employed in the Middle Ages, 133 Hunting and hawking in the feudal period, 131 LADIES hawking in the Middle Ages, 141 Lamp, a new, 315 Lamp, electric, self-regulating, 65 Lamp, Fiddian's, 80 Land leech, 239 Lava floods, source of, 175 Leam Moor, stone circles at, 347 Leather, compound for tanning, 386 Life, curious page of animal, 210 Light waves, 158 Linné and Aristarchus, 190 Literary notices, 74, 158, 237, 316, 392, 463 Loach, 412 Locket, new form of, 233 Lumbricidæ, 432 Lumbricus or earth-worm, 96 Lunar craters, 190 Lunar eclipses, 460 Lunar landscapes, 190 Lustre of fixed stars, 8 MADREPORARIA, 85, 241 Magnesia, sulphate of, manufacture of, 316 Magnolia in Greenland, 159 Making and applying aniline black, 235 Man, Isle of, stone circles in, 348 |