1SJ3.J 



THE CIVIL ENGINEER aND ARCHITECTS JOURNAL. 



437 



coal, lead to an empty globe from wliicli the air has been exhausted. The 

 two fluids on meeting produce a soft but most intense light. The 

 experiment was considered highly successful by the authorities who were 

 present, and it is to be repeated on a larger scale. Should the thing work as 

 well as in a general way as it did last night, and the cost be less than that of 

 gas, which it must he, there will be a dreadful revolution in gas works. A 

 company for supplying the electric light would realize a handsome profit on 

 charging only a sixth of what is now paid for gas. The strength of the elec- 

 tric light did not appear to exceed that of the hydro-oxygen ; but tlren how 

 much more simple is the apparatus; how much less costly the expense 

 of production ! The hydro-oxygen light requires a double and most 

 expensive apparatus, and is only applicable to a few localities ; the electric 

 light may lie applied externally and internally in any place. 



[The above description, copied from the French Journals, has been inserted 

 by many English papers, without comment, like several other paragraphs of 

 new and woiuierful inventions, which, if we are to believe them, are to su- 

 persede the present arrangements ; and yet, from that time forward, we 

 never hear anything more of them, they having been proved to be either per- 

 fectly impracticable, or. as is our opinion in the present instance, far more 

 expensive than that which is already in use ; conclusions to which every rea- 

 der could arrive at once, if the whole of the evidence were given instead of 

 ouly that portion which just suits the inventor or projector to give. Al- 

 though we consider that the consumption of nitric and sulphuric acids 

 and zinc, in 200 cells of a battery, would cost much more than the gas re- 

 quisite for the 20 lights which it is said to be equal to, we cannot state so for 

 certain without more data. But what we find most fault with is, the stating 

 that to he new, which has no novelty about it, and which every tyro in 

 galvanism has himself performed. The battery is an ordinary Grove's ar- 

 rangement, with charcoal substituted for the platinum, an improvement which 

 was made immediately after Grove's first announcement, and of which the 

 younger Silliuiau has long ago published a very simple arrangement. The 

 new light produced thereby between the charcoal poles, is almost as old as 

 the science itself, and is described in every treatise on the subject. Besides 

 which, in connexion with a cheaper battery, the whole process has been pa- 

 tented in this country with much better arrangements, and has not been 

 carried out, we suspect, on account, of the increased expense over gas. 

 As to the bad smell being given oft", there certainly is not at the light 

 itself, but at the proposed battery there are nitric acid fumes given oft", which 

 are not only offensive, but highly corrosive to anything it comes near, ani- 

 mal, vegetable, and mineral. It would he requisite to keep it in a place 

 by itself, if used in houses, as proposed, and then comes the increased 

 resistance to the cuirent produced by length of conducting wires. Al- 

 though well-disposed to encourage any plausible scheme for improving or 

 cheapening public lighting, we cannot, in the present instance, see much 

 to give us hopes of its success. At all events, we wish it to be stripped of a 

 claim which it does not possess, viz., untried novelty — and to place it in 

 the light of an experiment for public adoption, that which has been long 

 known and conducted both in the laboratory and at the lecture table. — 

 Editor C. E. & A. Journal."! 



NEW MANUFACTURE OK LIME. 



I'ateutcd by Messrs. Daniell and Hutchinson, May i, 1843; Specification 

 enrolled, November 4, 1843. 



Lime is at present usually manufactured from limestone, or chalk, or other 

 substances in which it exists in an indurated state, or state of solid combi- 

 nation with other bodies. The nature of Messrs. Daniell and Hutchinson's 

 invention consists in their having discovered that there are large tracts of 

 sand on the coasts of this kingdom, and particularly on the coasts of the 

 county of Cornwall, which are at present either treated as valueless or made 

 use of, like other sand, for purposes of mechanical intermixture merely, as in 

 the making of mortar, breaking up of tenacious soils, &c. ; but from which, 

 nevertheless, lime of an excellent quality, applicable to building, agricultural, 

 manufacturing, and other purposes, can be manufactured in large quantities. 

 The patentees state that they have ascertained, " by numerous and careful 

 analyses of the sand referred to, that it usually contains more than 70 per 

 cent, of carbonate of lime." The mode of reduction which they adopt is thus 

 described : — " In the first place, in order to test whether the sand on which 

 we propose to operate is of the proper quality, we put an ascertained quan- 

 tity into a retort, and pour dilute muriatic acid upon it ; if it contain car- 

 bonate of lime, a violent effervescence ensues, and carbonic acid is rapidly 

 evolved (the presence of which may be readily detected by its reddening 

 litmus paper.) "We then neutralize the muriatic acid by the addition of 

 liquid ammonia, and precipitate the lime by addiug the carbonate of ammonia 

 in excess. We next weigh this precipitate, which gives us a measure of the 

 average quantity of lime which may be extracted from larger quantities of the 

 sand of which that experimented upon was a sample. If the weight of the 

 precipitate is from six to eight tenth parts of the original weight of sand 

 tested, then the sand is of a proper quality for the purpose of our manufac- 

 ture ; but if much under that, the product will in some places not be sufficient 

 to defray the expenses of reduction. In manufacturing the lime on a large 

 scale, we proceed as follows: — we make use of reverberator? furnaces, vary- 

 ing in size according to the quantities operated upon, but the bodies of which 

 are generally from 20 to 30 feet in length, from to 10 feet in their greatest 



width, but gradually contracted towards the end, where they open into the 

 chimney, and from 13 inches to 2 feet in height. The sand is laid upon the 

 bed of the furnaces to the height of the bridges, which are made a little 

 higher than usual, in order that they may protect the sand from being blown 

 forward by the direct action of the current of flame upon them. The high 

 degree of heat to which the sand is here exposed expels the carbonic acid so 

 quickly, that in about two hours the process of conversion is generally per- 

 fected The lime is then withdrawn from the furnace through doorways 

 made at intervals, either in the sides, end, or bottom, for that purpose. It 

 is now in a proper state to be employed as a manure; but to fit it for the 

 various other purposes to which it may be applied, we first pass it through 

 tine sieves to separate any extraneous substances which it may contain." 



When it is desired to convert the lime so obtained into hydrate of lime, 

 the patentees add the necessary equivalent of water; if into sulphate of 

 lime, or gypsum, they add the necessary equivalent of sulphuric acid ; and so 

 on through all the various combinations of which lime is susceptible — 

 Mech. Mai/. 



MISCELLANEA 



North Shields. — The Old Gas Company. The North Shields Gat, works 

 have resolved to divide their capital stock into 1300 shares of 5/. each, and 

 to allot them in lots of not more than 10 shares each to gas consumers and 

 reduce the rates of burners and of gas to Is. per 1000 ft. from January 1st. 

 1844. The New Company " Borough of Tynemouth Gas Co." in which 1395 

 shares are taken by consumers, and 433 by non-consumers, offer to take the 

 prices the old company have reduced them to in Oct. 1844. The old com- 

 pany was established in 1821, and the new company assert that up to 1831 

 they were receiving 12| per cent, more than companies generally. Feeling 

 runs very high, and whether the truth of the adage of " two of a trade" 

 will be verified, time will show. 



Case of Lawastoopening out New Window Lights. — Atan adjourned 

 quarter sessions held at Guildhall, Newcastle-on-Tyne, October 30th, to de- 

 cide a dispute as to compensation to be paid to an individual by the corpora- 

 tion for setting his house back on a line with the other buildings. His house 

 projected before the adjoining house to the extent of 5^ feet. The adjoining 

 house was set back by the corporation thirty years ago. The counsel for 



the defence said : — " If Mr. had a right to windows in the side wall, 



why had he never had them there before. The fact was, that he could not 

 put out windows overlooking another person's property, and if he had made 

 windows in the side wall, the corporation, or the person whose property was 

 overlooked, could screen them up and obstruct the light. The plaintiff had 

 no right to ask compensation for a side frontage that did not belong to him, 

 and that he would not be permitted to have." The Recorder in summing 

 up said, " that there was only one point of law to which he would direct 

 the attention of the jury, which was, the right to put out windows on the 

 flank wall. He was of opinion the proprietor had not the right to do so 

 and, therefore, whatever benefit they might think would arise to the property 

 from having this additional light must be left out of the account in awarding 

 damages." It was a special jury case, and the offer of the corporation was 

 130/. the sum claimed was 900/. and the verdict 22.")/. The setting back of 

 the property was compulsory under the powers of a town improvement act. 



Newcastle-on-Tyne.- — There are now three projects for a high Level 

 Bridge at Newcastle, at least notices of intended application to Parliament 

 have been given, but the site as proposed by Mr. Green is that sanctioned by 

 Mr. Hudson, and Mr. Geo. Stephenson, the other two are by Mr. Grainger 

 and the Carlisle and Brandling Junction Railway. 



Chatham, Nov. 10. — The Admiralty have given directions for metal 

 mills to he erected in this dock-yard, similar to those at Portsmouth, for the 

 purpose of supplying the eastern yards with copper holts and sheets of copper. 

 It is also rumoured that the Admiralty have it in contemplation to enlarge 

 the yard, and also to make a large wet-dock for the reception of first-class 

 ships. The Watt steam-frigate is fast progressing, owing to the number of 

 hands on her. 



Flat Roofs. — Mr. I.oat of Clapham, builder, has lately obtained a patent 

 for what he calls an improved mode of constructing floors and roofs, which 

 are formed by a seties of hollow vessels of earthenware, that have been in 

 use for many years in forming arches ; hut instead of laying them with a 

 curve, Mr. Loat lays them flat on boards and combines them together with 

 cement, and when the roof or floor is completed and the cement set, the 

 boards are removed ; the upper suiface is covered with flat tiles or s'aK-s 

 bedded in cement. The under surface, be states, can he lathed with iron 

 laths or hoops, and plastered over with lime and hair; why not dispi 

 with the laths, would there not be sufficient key for the plastering with 



Paper Cloth. — Mr. Chapman of Arundel-street, Strand, lately obtained j. 

 patent for covering one or both sides of any fabric, such as canvas, muslin, 

 calico, or linen, with paper suitable for writing, printing, or drawing; it is 

 made by pressing the pulp on the fabric with a solution of gum. glue, or 

 other adhesive material, and passing it between rollers, by which mean 

 cloth and paper are firmly united. 



