138 



SCIENCE. 



[Vol. XV. No. 369 



arches as ordinarily constructed. The principal saving, how- 

 ever, is in the reduced number of beams used, owing to the con- 

 siderably greater span which may be made with the tile arch. 

 The prices for the work vary, of course, with the span and 

 number of courses, and also with the location and size of the 

 building under contract. 



The system is by no means an experimental one, as a large 

 number of buildings have already been erected with it, and 

 many others are in process of construction. Among notable 

 buildings in and near New York City, employing this method, 

 are the Mount Sinai Hospital, the Young Women's Christian 

 Association building, the Plaza Hotel, and the two new Edison 

 Electric Illuminating Company's buildings. The new Public 

 Library building at Boston is also being built by the system, 

 and some of the domed arches under construction are shown in 

 the accompanying engraving, made from a photograph. The 

 other engraving shows the arches in the Arion Club building at 

 Fifty-ninth Street and Park Avenue. In the Arion Club building 

 the arches are seventeen feet span. In the Young Women's 

 Christian Association building there are some arches of twenty- 

 nine feet span. The company is now erecting a building at 

 Fifty-seventh Street and Eleventh Avenue in this city, which 

 will have an arch of forty feet span for the roof. 



With these tile arches, some very fine architectural effects are 



foundation. At Secunderabad, in presence of the garrison and a 

 crowd of European and native spectators, he lately made an 

 ascent in his patent asbestos balloon. The inflation was effected 

 by the burning of methylated spirit inside the balloon, which was 

 held in place by twenty-five soldiers of the Bedford regiment 

 until the word to let go was given. After rising to a consider- 

 able height, the aeronaut descended by means of his parachute. 

 The spot where the ascent was made is over two thousand feet 

 above the level of the sea, and the achievement was all the more 

 remarkable because of the sultry climate and the great rarity of 

 the air. 



HEAT AND VENTILATION. 



To every man, woman, and child in this country this is an 

 important and interesting subject. Science has made more prog- 

 ress in almost every other direction than in this, and naturally 

 all improvements in heating and ventilating are carefully ex- 

 amined. The Hon. Hugh O'Brien, ex-mayor of Boston, at a 

 public meeting and in addi-essing the mayors of New England, 

 said, ' 'In my judgment, there cannot he found in the city of 

 Boston one single public building which could be considered as 

 properly ventilated, and I would strongly recommend a fair and 

 careful consideration of the Timby system of ventilating. ' ' 



This Timby system is now attracting universal attention. 



THE TIMBY SYSTEM OF HEATING AND VENTILATING. 



possible. Where it is desired to leave the sofBt of the arch 

 exposed, a special flanged tile can be used which shows no 

 joints when laid. Where desired, also, enamelled tiles can be 

 used for the soffit, of such color as the architect may desire. 



The great points of excellence claimed for this type of con- 

 struction, however, are cheapness and great strength. In the 

 construction of the Boston Public Library building, a heavy 

 iron column fell from a derrick, and went end first through one 

 of these arches. The arch, however, was not shattered by the 

 blow, but remained solid and unharmed except for the hole 

 broken out where the column went through. This system of 

 construction has been in use in Spain for a number of years, 

 and some notable buildings have been erected by it. One which 

 should interest factory-builders in this country is a one thou- 

 sand loom silk-mill at Barcelona, 371 feet by 330 feet in size. 

 The weaving-room occupies the whole of one floor, and its 

 arched ceiling is supported by 336 iron columns. 



WAE-BALLOONS. 



It has hitherto been generally believed that the Montgolfier 

 or hot-air balloon cannot be used in tropical climates. If this 

 were true, ballooning for war purposes would of coui-se be im- 

 possible in places where coal-gas could not be obtained. We 

 learn from the London Times that Mr. Percival Spencer, who has 

 been making a series of interesting balloon expei'iments in Cen- 

 tral India, has succeeded in showing that the theory is without 



especially in New England, and we are gi-atified^o be able'to 

 present to our readers the plan given hei-ewith, showing the 

 manner in which this system is introduced. It is applied here 

 as a street system, pure heated air being inti-oduced into all the 

 houses on a line of street from a centi'ally located plant, precisely 

 as gas and water are inti-oduced. Pure fresh air is received 

 through a pipe at an elevation above the sun-ounding houses, and 

 this air is driven by a fan through a conduit, and over pipes 

 filled with hot water, at such a pressure as admits of its being 

 distributed into all the apartments of any house on the line. 

 This heat being regulated by a register in the various rooms, the 

 temperature can be secured as desired. Not only can this be ac- 

 complished, but, when so desired, the air can be cooled; so that 

 in Southern climes, or during heated terms, each house on the 

 route can be made perfectly comfortable. So much for the street 

 or city system. 



When required for a single building, say a schoolhouse, church, 

 or hospital, the plant can be placed in the basement, and the fresh 

 air brought from above, driven in the same manner into all the 

 rooms, heated or cooled as desired. When necessary, a disin- 

 fectant can be used, and a block of houses, a street, or city 

 thoroughly fumigated in a few minutes. The adoption of the 

 Timby system for our schoolhouses will insure to every scholar 

 the amount of fresh air changed as required, which at present is 

 the crying want of our educational system. 



With the great progress in cooking by gas, it is not uirreason- 

 able to suppose that eventually the demand for fuel for use in 



