Page:Hardwicke's Science-Gossip - Volume 1.pdf/202
BOTANY.
Possible Increase of an Orchid.—An acre of land would hold 174,240 plants of the spotted orchis (Orchis maculata), each having a space of six inches square, which is rather closer than they could flourish together; so that, allowing twelve thousand bad seeds, and acre would be thicky clothed by the progeny of a single plant. At the same rate of increase, the grandchildren would cover a space slightly exceeding the island of Anglesea; and the great-grandchildren of a single plant would nearly clothe with one uniform green carpet the entire surface of the land throughout the globe.—Darwin's "Fertilization of Orchids."
Ancient Trees.—The celebrated chestnut (Castanea vesca) on Ætna must be a thousand years old at least. The Baobab trees (Adansonia digitata) of the Green Cape demand of us, according to their thickness and the number of zones in some of their branches, and age of 4,000 years or thereabouts. The gigantic cypress (Cupressus disticha) at Santa Maria del Tule, six miles east of Oaxaca, in Mexico, has a circumference of 124 Spanish feet, about 40' in diameter. Now, suppose that every annual zone measured 1''', the tree must be nearly 3,000 years old. It is historically certain that it is older than the conquest of Mexico by the Spaniards. The age of the great dragon-tree (Dracæna draco) at Orotava, in Teneriffe, is supposed to be 5,000 years. These examples are quite sufficient to prove the possibility of a compounds plant living on without end.—Schleiden's "Principles of Scientific Botany."
Twining Plants.—A greater number of twiners revolve in a course opposed to that of the sun, or to the hands of a watch, than in the reverse course, and, consequently, the majority, as is well known, ascend their supports from left to right. Occasionally, though rarely, plants of the same order twine in opposite directions, of which Mohl gives a case in the Leguminosæ, and we have seen another in Acanthaceæ. At present no instance is known of two species of the same genus twining in opposite directions; and this is a singular fact, because different individuals of the Bitter-sweet (Solanum Dulcamara) revolve and twine in both directions: this plant, however, is a most feeble twiner.—Darwin on Climbing Plants.
British Lichens.—The Rev. W. A. Leighton has commenced a series of papers, to appear from time to time in the Annals of Natural History, containing notes and illustrations of new or recently discovered British lichens, or such as have not been figured and described in Sowerby's "English Botany." The first paper was published in No. 91, for July, 1865.
Brittle India-Rubber.—Mr. Spiller has recently shown (Chemical Society, February 16, 1865), in a paper on the oxidation of India-rubber, that this substance, when exposed to the air in a fine state of division, gradually becomes converted into brittle resinous matter, very similar to shell-lac.
To Dry Flowers with their Natural Colours—"A vessel with a moveable cover is provided, and having removed the cover from it, a piece of metallic gauze of moderate fineness is fixed over it, and the cover replaced. A quantity of sand is then taken sufficient to fill the vessel, and passed through a sieve into an iron pot, where it is stearine, carefully stirred, so as to thoroughly mix the ingredients. The quantity of stearine to be added is at the rate of half a pound to one hundred pounds of sand. Care must be taken to add too much, as it would sink to the bottom and injure the flowers. The vessel with its cover on, and the gauze beneath it, is then turned upside down, and the bottom being removed, the flowers to be operated upon are carefully placed on the gauze, and the sand gently poured in, so as to cover the flowers entirely, the leaves being thus prevented from touching each other. The vessel is then put in a hot place, such, for instance, as the top of a baker's oven, where it is left for forty-eight hours. The flowers thus become dried, and they retain their natural colours. The vessel still remaining bottom upwards, the lid is taken off, and the sand runs away through the gauze, leaving the flowers uninjured."—Journal of Society of Arts.
The Periwinkle.—But for all wonder-working herbs commend us to that seeming simple inhabitant of our gardens, the periwinkle. The list of virtues belonging to this wort are completely overwhelming; and if one's whole lifetime were devoted to the plucking and distributing of this herb amongst one's fellow-creatures, it would scarcely be wasted—only supposing the Saxon herald of the magician periwinkle to have spoken sooth. "This wort, which is named priapiscus, and by another name vinca pervinca, is of good advantage for many purposes; that is to say, first, against devil-sickness, and against snakes, and against wild beasts, and for various wishes, and for envy, and for terror, and that thou may have grace: and if thou hast this wort with thee, thou shalt be prosperous, and ever acceptable."—Once a Week.
Pollen of Crowfoot.—Mr. G. Gulliver has called attention to the difference in the pollen grains of all the British species of yellow-flowered Ranunculæ with divided leaves. The variations in size lie between th and th of an inch in diameter in the six species examined. Those of the Corn Crowfoot are rough, whilst those of the others are smooth.
