MISCELLANEOUS.

Globe, Volume XX, Issue 1568, 27 February 1879, Page 3

MISCELLANEOUS.

From what occurred the other day in Boston, according to the “ Daily Advertiser,” it is wise for residents of new houses that they should keep close watch of the fireplaces during their first trial. The fi e in the Roberta mansion on Beacon Hill, which was about three years in building, and had the immediate supervision of an architect, is an item of grave astonishment not only to the underwriters, but to th owner. Two days previously a fire was started in one of the open grates for the first time, and not burning freely was dumped upon the hearth. From that moment there was a smell of smoke in the apartment, when, as above noted, it was discovered that the hearthstone rested upon a beam which ran directly across the fireplace. About three feet of this beam was burned off. Three other Boston fires from open grates are noted within a fortnight, A South-end resident had an attractive soapstone fireplace, and, purchasing a pair of end-irons, started an old-fashioned wood fire, to find that his fireplace was only a ventilation, and his blaze burning in behind the plastering np through his house. Another case similar was the Marlborough street fire in October, where a single course of brick for a hearth resting upon the beams was no protection, and a marble slab for a hearth lying upon the under floor being overheated set the floor afire.

Apropos of illuminated watch faces and clock dials, to which attention has recently been directed, M, Recordon, of Paris, communicates the fact to one of our French exchanges that two years ago he took out a patent for, and has since been manufacturing, illuminated dials on an entirely different principle from those produced by the use of chemicals. His device is this A Geissler tube containing a gas which gives a brilliant light is placed on the dial; a battery about the size of a thimble is attached a» an ornament to the wath chain, and a miniature induction coil is also hidden in the latter. When it becomes desirable to consult the watch in the dark, a spring is pressed, the current passes into the coil, then into the Geissler tube, and illuminates the dial. The portable battery used for this purpose is that of Trouvb, which, in a small compass, has considerable strength. Reduced to the size of a thimble, it is still sufficiently strong in its action to Isst a year, M. Recordon also applies the same principle to the illumination of clock faces.

A very valuable cement has been discovered by Mr A. 0. Fox, of which details are published in “ Dingler’s Polytechnisches Journal.” It consists of a chromium prepara! ion and isinglass, and forms a solid cement, which is not only insoluble in hot and cold water, but even in steam, while neither acids or alkalies have any action upon it. The chromium preparation and the isinglass or gelatin do not come into contact until the moment the cement is desired, and when applied to adhesive envelopes, for which the author holds it to be especially adapted, the one material is put on the envelope covered by the flap (and therefore not touched by the tongue), while the isinglass, dissolved in acetic acid, is applied under the flap. The chromium preparation is made by dissolving chryatallised chromic acid in water. You take :

Cyrystallised chromic acid 2.5 grammes. Water 15 ~ Ammonia 15 ~ To this solution about 10 drops of sulphuric acid are added, and finally 30 grammes of sulphate of ammonia and 4 grammes of fine white paper. In the case of envelopes, this is applied to that portion lying under the flap, while the solution prepared by dissolving isinglass in dilute acetic acid (1 i>art acid to 7 parts water) is applied to the flap of the envelope. The latter is moistened, and then is pressed down upon the chromic preparation, when the two unite, forming, as we have said, a firm and insoluble cement.

The Philadelphia Local Telegraph Company has perfected an arrangement putting their clients in the various parts of the city into immediate telephonic connection. This is done by means of an ingenious telephonic switch board recently devised. As described by a local paper, the f ront of the apparatus consists of a walnut frame and bright strips of brass, punctured with holes, into which wires are fitted to make the necessary connect ons. Behind this all the wires converging in the office concentrate. The board just put in operation accommodates no leas than 400 different lines, which have an aggregate length of 1000 miles, thus placing each firm or individual having telephonic connection with the main office in direct communication with 399 other persons scattered over the city. Should an individual at the Baldwin works desire to converse with a person at Cramp’s shipyard, he ascertains from a printed card the number or call of the Kensington shipbuilders. As an instance, if the number of the Cramp telephone is 12, the speaker at Baldwin’s touches a spring attached to his instrument to designate the number, and immediately a bell at the central office rings out the signal, and simultaneously a little tablet on the switch board drops and reveals the name of Baldwin and Co. An attendant sees at a glance that some one at Baldwin’s desires to talk with No. 12, and, finding this to be the box at the Cramp yards, connects the wires of the two places, either by means of the pins referred to or by joining them to a rod fixed in the back of the switch board. Now. the man at Baldwin’s practically has his mouth to the i ar of the person at Cramp’s, and can talk to him about the weather, or the price of steamships, or order some machinery, or invite him to dinner, as he chooses. If he wants tome article which the shipbuilder cannot supply, they may recommend him to one of the oilier 398 establishments conn cted with the telephone exchange, and, by going through the same aim) le process, he can order coal at Port Richmond, call for cars at Washington street wharf, send for a man at Manayunk, and, in fact, can talk with a dozen individuals in as many di-tant points in less than that number of minutes. The instrument is so arranged that any number of persons can talk on as many subjects at the same time, from different points, without experiencing the difficulty that occurred at the building of the Tower of Babel. Telephone circuits, working [substantially similar to the above, are now in operation in the principal cities of the United .States. A very important application of the electric current, says the “ British Trade Journal,” is now being carried out by Sir William Armstrong on his estate, A volume

of wat,‘t descending at the outfall cf a Northumberland lake has been utilised by the interposition of a turbine, by means of which the requisite revolutions are given to a dynamo electric machine. The electric current thus generated is conveyed through a stout copper wire to the private residence of Sir William at Cragside-a distance of ab ut a mile and a half. The current is there conducted through a lamp, in which the regularity of the light is maintained by clockwork, subject to the control of an electro magnet, which magnet reflects the strength or weakness of the current, so as to regulute the distance between the points of the carbon electrodes. It has been found necessary to provide a second wire to take the return current, so that the first cost of the light is somewhat large, but the working expense is very small. In addition to this use of the electric current as a source of light, Sir W. Armstrong intends to avail himself of the power thus brought into his house by applying it to several domestic purposes. This is to be accomplished bv means of an electric engine situated in or near the house, and receiving the current transmitted from the machine at the lake outfall. In this way Sir Wm. will be able to make a more constant use of what may be termed his electrical “plant,” and thus may look forward to a satisfactory result in an economical respect. This example of the conversion and transmission of power will be viewed with great interest, the distance of a mile and a half being sufficient to indicate a much more extended sphere of action for the electric current than has hitherto been found prac icable.