566 



TEE POPULAR SCIENCE MONTHLY. 



complislicd by affixing to one side of the 

 tub a perforated shower-tube connected with 

 the hot and cold water supplies. The bather 

 sits upon a chair at the foot of the tub, en- 

 veloped in a curtain of rubber cloth, with 

 an attachment extending over the tub. He 

 is thus assured the full benefit of all the 

 evaporation from the hot water, -uiiile 

 his face is totally shut off from it, so 

 tliat he does not breathe any of it. By 

 means of another ecjually simple attachment, 

 substances with which it may be desired to 

 medicate the bath are brought into contact 

 with the water and made to mingle their 

 fumes with the steam. This form of bath, 

 which has all the advantages of the Russian 

 bath, and is, moreover, adapted to domestic 

 use, has been introduced into a great many 

 houses in New York and other places, as well 

 as into hotels and public institutions, and is 

 highly recommended by those who have em- 

 ployed it or examined it. In another form of 

 apparatus, sold by J. Allen & Sons, of Lon- 

 don, the lamp is placed outside of the cur- 

 tain, within which the vapor is conducted 

 by a pipe. The whole apparatus can be 

 packed into a box less than twelve inches 

 square. An arrangement is also furnished 

 by which the vapors are introduced into the 

 bed in which a patient may be lying; or 

 the lamp, if preferred, may be put directly 

 under the chair. This bath has received 

 medals and high awards at several "health " 

 or "sanitary" exiiibitions. 



A Snn-hoatinK Apparatus for Rooms. — 



Professor Edward S. Morse, of Salem, Mas- 

 sachusetts, has tried the experiment of call- 

 ing in the heat of the sun to assist in warm- 

 ing and ventilating his house. lie attaches 

 to the wall of his house a box nearly the 

 height of the story, about three feet wide, 

 and of suitable depth, and so arranged and 

 connected with openings in the wall as to 

 act as a flue. The outside of the box is 

 made of slate or black corrugated iron, sub- 

 stances wliich absorb heat, and over this is 

 a " window " of glass. "With this apparatus, 

 the air in a room measuring twenty-one by 

 thirteen by nine feet, could be changed 

 in forty-five or fifty minutes, and a very 

 perceptible degree of warmth was obtained. 

 A similar heater, forty-two feet long and 

 six and a half feet wide, attached to the 



Boston Athenaeum, is estimated to do work 

 that would ordinarily require between twen- 

 ty-five and fifty pounds of coal a day. 



Earthqnake-proofBnildlnj;s. — The com- 

 mittee of the British Association appointed 

 to investigate the earthquake phenomena of 

 Japan, after reporting upon their experi- 

 ments into the nature of the vibrations of 

 the ground, offer some suggestions on the 

 construction of earthquake-proof houses. 

 In a house resting at its foundations on cast- 

 iron balls, the measuring instrument showed 

 that, although considerable movement took 

 place at the time of an earthquake, all sud- 

 den motion had been destroyed ; but wind 

 and other causes produced movements of a 

 far more serious character than the earth- 

 quake. To give greater steadiness to the 

 house, eight-inch balls were tried, and then 

 one-inch balls. Finally the house was rest- 

 ed, at each of its piers, upon a handful of 

 cast-iron shot, each one fourth of an inch in 

 diameter. By this means the building has 

 been made astatic, and, in consequence of 

 the greater increase in rolling-friction, suf- 

 ficiently stable to resist all effects like those 

 of wind. The shot rest between flat iron 

 plates. When erecting a building in a re- 

 gion subject to earthquakes, it appears that 

 we ought first to reduce, as far as possible, 

 the quantity of motion w hich ordinary build- 

 ings receive; and, second, to construct a 

 building so that it will resist that portion of 

 the momentum which we are unable to keep 

 out. To reduce the momentum we may — 

 1. Select a site where experiment shows 

 that the motion is relatively small. 2. For 

 heavy buildings, adopt deep foundations 

 (perhaps with lateral freedom), or, at least, 

 let the building be founded on the hardest 

 and most solid ground. 3. For light build- 

 ings, put in the shot foundations. As against 

 the momentum which can not be cut off 

 from the building, it should be borne in 

 mind that it is chiefly stresses and strains 

 which are applied horizontally to a building 

 that have to be encountered. A vertical 

 line of openings, as in doors and windows 

 in a building, constitutes a vertical line of 

 weakness to horizontally applied forces. 

 Avoid coupling together two portions of a 

 building which have two vibrational peri- 

 ods, or which, from their position, are not 



