The celebrated John Wesley recommended rubbing the part morning and evening with a raw onion until it became red, and then applying a little honey. The vendors of Rowland’s ‘Macassar Oil’ recommend the head to be rubbed with a towel (or hair-brush), until somewhat red, each time before applying their nostrum; and the advice is certainly good, as independent of the stimulus thus given to the skin, and the increased flow of blood through the minute vessels of the scalp, it is rendered more absorbent and sensitive to the action of medicaments. At the same time the reader must be cautioned against placing any reliance on external applications, unless he assists their action by due attention to diet, exercise, ventilation, and such other matters as tend to promote the general health and vigour of the body.
The substances usually employed to medicate hair-cosmetics, the general management of the hair, and the formulæ for various applications to promote its growth, preservation, and beauty, are noticed in the articles Hair, Hair-cosmetics, Pomades, Oils, Washes, &c., to which the reader is referred.
BALEEN′ (-lēne′). [Fr. baleine.] The fisher’s name for whalebone.
BALL (bawl). [Eng., Ger., Swed.] Syn. Balle, Boule, Fr.; Bal, Bol, Dau.; Glob-u-lus, Pi′la, L. In commerce, veterinary medicine, perfumery, &c., applied to various substances made up into a globular, spheroidal, or even a cylindrical form, as ash-balls, horse-balls, soap-balls, &c.
BALLOON′ (-lōōn’). Syn. Ballon, Fr., Ger. Any hollow spherical body of which the sides are extremely thin or attenuated in comparison with its diameter or bulk. In aërostatics, a machine or apparatus for elevating and sustaining bodies in the air. In chemistry, a globular glass-receiver, with either one or two necks (= GROS RÉCIEIENT, Fr.; GROSSE R., Ger.). In pyrotechny, a hollow case or ball of pasteboard filled with fire-works or combustibles, which explodes in the air on being fired from a mortar.
Balloon. In aërostation, a bag or hollow pear-shaped vessel, made of varnished silk or other light material, and inflated with some gas or vapour lighter than the air, as hydrogen, carburetted hydrogen, heated air, &c., so as to rise and float in the atmosphere. When filled with gas it is called by way of distinction an AIR-BALLOON (aérostat, &c., Fr., lufball, luft-schiff, &c., Ger.); when with heated air, a FIRE-BALLOON or Montgolfier b. (ballon à feu, &c., Fr.).
In the early days of aërostation, and indeed for some years afterwards, balloons were inflated with hydrogen gas, obtained by the action of sulphuric acid and water on iron filings or small fragments of iron; but this method of filing them ultimately gave place to the cheaper and more convenient supply afforded by the gas-light companies. Of late years, the coal-gas furnished by the gas-works has been generally, if not solely, used for the inflation of balloons.
The principles of ballooning may be referred to the well-known difference in the specific gravity of bodies, and to the physical properties of the atmosphere. Pure hydrogen, weighed at the level of the sea, is about 16 times lighter than common air; but when prepared on the large scale, and containing water, and other impurities, it is only from 7 to 11 times lighter than the atmosphere. A globe of atmospheric air of 1 foot in diameter, under like circumstances, weighs 1⁄25 lb.; a similar globe of hydrogen (reckoning it only as 6 times lighter than common air, will, therefore, have an ascensional force of 1⁄30 lb.). Now, the weight of the body of air which a balloon displaces must exceed the gross weight of the balloon and all its appendages, in order for the latter to ascend in the atmosphere. The difference of the two weights expresses the ascensional force. The aërostatic power of balloons is proportional to their dimensions, in the ratio of the cubes of their diameters. Thus, it appears that a balloon of 60 feet diameter filled with common hydrogen will ascend with a weight of nearly 7000 lbs., besides the gas case; whilst one of only 1½ foot in diameter will barely float, owing to the less proportionate volume of gas to the weight of the case containing it. In round numbers the buoyancy of a balloon may be reckoned as equal to 1 oz.
for every cubic foot of hydrogen it contains, less the weight of the case and appendages. The carburetted hydrogen supplied by the gas-works is much heavier than hydrogen gas, and consequently much less buoyant, for which due allowance must be made. That which possesses the least illuminating power is the lightest, and consequently the best adapted for aërostation.
The fabric of which the cases of air-balloons are made is strong thin silk, covered with an elastic varnish of drying oil or india rubber, or, what is better, a solution of india rubber in either chloroform or bisulphide of carbon; the netting is of strong light silk or flaxen cord; and the car of basket-work. Fire-balloons, on the small scale, are generally made of silver-paper, and are inflated with the fumes of burning spirit of wine, by means of a sponge dipped in that liquid, and suspended just within the mouth of the apparatus.