Science Sittings

New Zealand Tablet, Volume XXXIII, Issue 34, 24 August 1905, Page 29

Science Sittings

By 'Volt'

British Inventions

The recent classification at the British Patent Office shows that cooking is the popular subject of invention, having been the subject of 3575 British patents in 48 years, or an average of 73 a year. Umbrellas brought out 1457 inventions, and hats 1411. Invention tends, to run in grooves, 1896 and 1897 reflecting the enormous development in cycles, while motor vehicle inventions have doubled since 1900.

Appendicitis.

While foreign bodies in the vermiform appendix are not rare, they do not seem to have the effects formerly attributed to them. In 1600 post mortem examinations Dr. L. J. Mitchell, a coroner's physician, has found one or more grape seeds in the appendix in eight cases, one or more shot in three cases, fragments of bone in two cases?, and in single cases such objects as a piece of a shingle nail, a globule of solder, a piece of nutshell, and bits of ash or stone. In no case was any evidence of inflammation of the appendix, past or present, to be found.

Classification of Woods

Wood, is classed as hard or soft, the main difference between these classes being that the soft wood tree has ' needle leaves '—slim, narrow, and almost uniform in breadth— while the hard wood tree has leaves of various shapes. Some soft wood trees bear cones— are conifers. Resin is more characteristic of soft than hard wood. To the class of soft woods belong the pines, spruces, and firs, and the most common examples are yellow pine, white fir, pitch pine, and spruce, or red fir. The commoner hard woods are the oak, beech, mahogany, ash, walnut, plane, elm, birch, and ebony.

Wonderful Silk of the Spider

The astronomer after the experience of many years has found that the spider furnishes the only thread which can be successfully used in carrying on his work, writes Ambrose Swavey in the ' Scientific American.' The sipider lines mostly used are from one-fifth to oneseventh of a, thousandth of an inch in diameter, and, in addition to their strength and elasticity, they have the peculiar property of withstanding great changes of temperature ; and often when measuring the sun spots, although the hoat is so intense as to crack the lenses of the micrometer eye piece, yet the spider lines are not in the least injured. The threads of the silkworm, although of great value as a commercial product, are so coarse and rough compared with the silk of the spider that they cannot be used in such instruments. Spider lires, although but a fraction of a thousandth of an inch in diameter, are made up of several thousands of microscopic streams of fluid, which unite and form a single line, and it is because of this that they remain true aiK] round under the highest magnifying power. An instance of the durability of the spider lines is found at the Allegheny Obsenatory, where the same set of lines in the micrometer of the transit instrument has been in use since 1859.

Why People Blush

The blush is masculine rather than feminine. Such, at all e\ents, is the opinion of an eminent French scientist, Professor Eulouard Guyot, says ' Science Siftings,' who has made some quite elaborate experiments with a \iew to deciding the question. It is generally supposed that blushing is a symptom of modesty ; but it seems that this is a mistake. Persons of little or no modesty "blush as often as the most innocent and guileless, and men are much more given to the habit than women. In either sex, however, blushes are most frequent in youth, and they tend to" become steadily more rare as age advances. A blush, explains Prolessor Guyot, originates in the brain, through the effect of some mental impression ; the brain telegraphs through the sympathetic nerves to the muscles that control the small blood vessels which carry red blood (the blood when it flows through the veins is blue) and the crimson fluid rushes to the surface of the body. It is always an involuntary performance.