'2i> 



THE CIVIL KNGINEEll AND ARCM1TECT\S JOURNAL. 



[January, 



III' ils iuiilslil|i^t'elion -183- Miiiaic iiiilu".. In each c.vpcriinciit llie wiiuli was 

 ilrixcn Ijy two men. 



('iiiirliisiiiiis. — I'roiii tlie preeeiling talile il ajiiiears tliat tlie relative merits 

 cif the serew |irii|ieller, tlie eoaoidal iiro]ieller, ami (lie ednimini and Irapezium- 

 >liapeil iliiats are ]ireei.-elv in the order in which the\ stand in the talile; tliat 

 the seiiM is infeiiiir to the eiininnm ]iadd!e-\\heel in the ratio of '^'^ to 2S, 

 with the s]iear-pointeil paddle^ as 'l-'l to '2-'.l, ami with theeonoidal propeller 

 as 2-2 to 3-3 ; tlial of (he trapezium-shaped tloals as 28 to 2-0, and that witli 

 the ol)tuse angle down is ei|nal. It may he olijeotcd to these experiments, 

 that the hoat lieiiig worked hy men, the rcsidts cannot he de]iciideil iipmi.on 

 account of the irru:-;nlar, and, pcrliaps, over-zcalons netion of aiiinial )iower. 

 nut, alicr a few trials, the action soon hecomes as rei^ular, and may he cal- 

 tul,''.ted upfiU with nearly the same accuracy, as a steani-eniiine. 



'li.ii'Jly — liy means of a sleam-lioat. This hoat was kindly h nt hy the 

 loiidun and Westminster Steatu-boat Company; ami is of the following- 

 diiiien^ious ; — 



Length -u feet. 



Breadth C feel. 



Depth 3 feet. 



Power — two engines (vibrating) of .'i horse power — 3(! strokes 

 per minute. 

 Talh in ivhich are comparfd the Performances of Reclmiynlar and Sjiear- 

 s/iaped Floats, with tite " I'ink" steamer, in the ll'est India Import Dnci-, 

 in November, 1839. 



Conf/iisioiif!. — From the residts of these experiments we are justified in 

 concluding that the trapezium-shaped float, containing only one-half of the 

 surface of the eommon jiaddle, and one-third of its w idtli, will have equal hold 

 of the water, and propel llie vejsel equally as favt, with a less expenditure of 

 power ; hut its properties arc not only confined to this. 



In the first iilaec, they are less weight and first cost, by at least one-half. 



Secondly — 'I'liey present less surface the wind, |iarticularly against a head- 

 wind. 



'I'birdly — They enter the water without lite shock and \ihratioiis which are 

 experienced wilh the eoniuion wlieid, and without laising tin! cascade of 

 water aiijiertainiiig to the old form of p.nddle. 



I'onrtbly — 'l'lie\ woik nearly as well when dec|ily immersed, with the ex- 

 ception of the slight resistance arising from the edges of the amis. 



All which properties have been witnessed and tested hy competent judges 



C;,\S PRODUCED liY A NEW PROCESS. 



.■\.\ cxiierinieiit in gas-lighting by the Cimite de Val Marino was made on 

 Thursday evening on a jiieee of waste ground at the hack of I'etter-latie, in 

 the presence of :e\eral scientific gentlemen, who were invited to v\itness the 

 result. A small gasometer vvasen-eted for the purpose, which was connected 

 l)y tubes with a fiunaee hnilt of btiik, and roiitaiiiing thice ri'torts, one of 

 which was supplied with water fjoni a sipbon, another was filled with tar, 

 and both being decomposed in the tbii'd retort, formed the sole materials by 

 which the gas was iiroduced. The process ;ippeaied In he extremely simple, 

 and IbiMiovelty of the experiment consisted in the fact, (hat the principal 

 agent rmployed to produce the gas v\as ennimon water <iiMiliijied with tar; 

 but, aecordiii!-' to the tlief.r) of the iiiveiilor of this new species of gas, any 

 sort of bituniiiious or fatty matter would answer the purpose ei|iially as well 

 as pitch or tar. After the lapse of about half an hour employed in the ex|ie- 

 riment, diiiiiig xvhii'h time the process was explained til Ihii company, the 

 gas was turned inlii the hurncrs.and a pure ami jiowerfnl light was produced, 

 perfectly free from smoke or »7iy uiiiilca.^.i.nt smell. The puilty anil inlensc- 

 ncss of the flame were testeil iu ti very salinfuetory manner, and those who 

 witnessed the experiuient apjiearcd perft/clly ^allblted with the result. The 

 great advantage of this sort of gas over that produi'cd from coal consists, it 

 ■tvas said, in the cheapness of the materials employed in its production, the 

 facility with which it is m.anufactnred, and the perfection to which it is at 

 Onee brought, withotit (he necessity of its undergoing the tcdigns and expen- 



sive process of coiidettsation and purification; for in this instance, as soon as 

 the iircliminaries were com|>leted, the Ught was produced in a jierfcct state 

 vwthin a fi'w feet of the gnhomeler, which, allbougb of inferior si.'C, was said 

 to he capable of ;ilfording light for 10 hours to at least .'>00 lamps or hurners. 

 A\"itli regard to the coniiiarative expense, it was also stated that 1000 cubic 

 feel of gas maunfaetured hy this jiroeess, could be su|iiilied to the public for 

 about one third the price now charged by the coal-gas companies; and it 

 was said to he cipially available for domestic use, and more safe than the 

 common gas, inasmuch as small gasometers might, at a trifling exjiensc, be 

 fixed at the hack' of grates in ]iriva(o dwellings, from which the gas could be 

 conveyed in India-rubber bags to any part of the bouse, thereby ]ireveuting 

 the many accidents which occur by (he use of tubes and pipes. The fViunt 

 de \u\ Marino, who has eoni|Uered the diflicnlty hitherto experienced in 

 bringing this spiTics of gas into use, superintcuded the arrangements, and 

 evinccil a natural anxiety to bring bis experiment to a successful issue, lie 

 has taken out a j>atent for bis discovery, and be has im])roved upon the 

 burners now in use, so as to render the light jirodnced more ]mre and intense. 

 For this inqirovement he is also secured hy a patent. How far gas of this 

 descri[)tiou can he brought into general use, or whether in point of economy 

 the public would he benefited by its ado\ilion, are questions which we have 

 not the means of deciding, and, without liazarding any opinion on the sub- 

 ject, vvc can only say that the experiment, as far as it was tried iu this instance, 

 appeared to be quite successful. — Times. 



AMERICAN PATENTS. 

 (From tlie Juiirnal of the Franklin Institute.) 



For " An imjirored Eccentric Brukc, for urrestiny the motion of Railroad 

 Cars." Ephraim Morris, lUoomfield, Essex county. New Jersey, Scjit. 10. 



ISctween the two wheels on each side of a car there is to be a cam wheel, 

 one pari of which is to he a segment of a circle, resendding the periphery of 

 one of the wheels ; another portion of the periphery of the cam is in a straight 

 line, ]irobably of two feet or more in length, and the cam may be made to 

 roll round on its circular, or curved jiart, and to bring this slraight part upon 

 (be rail, which, whilst it bears 0)1011 it, will lift the wheels, at one or both 

 ends, Iherefrnm. The straight portion of the cams are furnished with flanches 

 which embrace the rail. This iiart, by its friction ujion the rail, is to operate 

 as a brake upon an inclined plane, or elsewhere. The claim is to the fore- 

 going aiTangcment of the resiicctive parts. 



When it is desired to relieve the brake, this is ctfceted by backing the cars, 

 when the ordinary wheels arc ni.ade to rest ui>on the rail, the lower side of 

 the brake being then free from them ; there are, of course, some jiarticular 

 devices described which we have not noticed, nor do we think it necessary, 

 being apprehensive that the contrivance is not destined to be adopted. 



For "J Machine for cuttinij the Teeth of Cireular Saws." Tbaddeus Sel- 

 lick, llavcrstraw, Rockland county. New York, September 19. 



One, two, or more, steel plates, prepared to have teeth cut upon them, are 

 to be placed upon a vertical siiindle capable of revolving on its two ends. 

 These plates arc to be made to beai' against a revolving cutter, consisting of 

 an endless screw, the thread of which is in such form as to cut a saw tooth. 

 A cutter two inches iu diameter and half an inch in thickness, has been used 

 for the purpose. The revolution of the cutter will c.iuse that of the saw 

 plates, which arc hin-ne U|i against it. It is remarked that the teeth of straight 

 saws ma)' he cut by a similar device. 



" M'b.il I claim, is the cniiiloyuient of a circular revnlvhig cutter, having 

 a thread or channel on ils |ieriphery, running in the manner of an endless 

 screw, and so arranged and combined with tlie other jiarts of the inachiuery 

 eiO|doyed, as to cause (he cutter to cut, and (0 feed (be |ilates to itself, by 

 its oxvn action, the whole operating stdistantially in the m.iuncr above set 

 forth." 



For " .//( Ini/irorenient in the mode of preserriny Timber." Edward Earl, 

 Savannah, fleorgia, September 20. 



We iiublished in our last iiniuhcr, the specification of a patent for n similar 

 puiiinse. the gentleinan above named being one of the patentees. The mode 

 of iiroeednre in the ]u-eseiit case is like that deserihed in the former jutcnt ; 

 that is, the timber is (o be boiled in (be sohidon by which (be preservadve 

 (piality is to he eommuuieatcil, which solution is (o consist of sulphate of 

 copper, (blue vitriol,) and sulphate of iron, (copperas,) dissolved in water. 

 One jiart of snliib.ate of copper to three of sulphate of iron, are to be taken, 

 and about three jionnds of the mixed salts added to every gallon of water. 

 The timber after being bored through its length, is to be boiled, and after- 

 wards sufl'cred (o cool in this solution. The claims made, are to " the boil- 

 ing of timber as described, iu a solution of sulphates of iron and of copper ; 

 apiilyiug this solution to the interior as well as the exterior of the timber, by 

 means iif the central perforation when (he size of the timber requires it, as 

 the most clh'ctnal mode of jirotecting it from the rav.ages of insects, and of 

 rot. I do not claim the saturating of timber by a solution of sulidiates in 

 water when aii|died cold, but confine my claim (o boiling it, as above set 

 forth, in (hat solulion, during from two to five or six hours, or more." 



For " A Grncel Pnm;!." l.aura Rice, adnunistr.atrix of J. J. Rice, and 

 Ebeaezer Rice, Salina, New York, August 15. 



" This pump, or machine, is inserted in a wcU, or shaft, which should be 



