318 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



[|NoVEMBEB, 



Mechanics' Fairs of the United States give tliem precedency of us. 

 The provincial flocks to the extii()ition of ni-ichinery, or the hazaar 

 for tlio inec-lianics' institution, as he dues to the great metropolis: 

 but hitherto tliere has been no sufficient temptation to open such 

 exiiihition. Tlie gallery formed in tlie King's Mews by Mr. 

 Charles I'ayne, and the Polytechnic Institution, were botli pro- 

 jected on a scale too inconsiderable to f(nin a complete national 

 exhibition; and the reliance was rather on tlie publication of 

 novelties than in the formation of a full collection of everything 

 <dd and new. Indeed, the call on the Polytechnic Institution is 

 for novelty; and the metropolitan population support it to a much 

 smaller extent than is supposed. To them tlie shops are open — 

 Woolwich, Chatham, the Mint, the shipyards, lirewcries, gasworks, 

 marbleworks, saw-mills, docks, railway stations, telegraph stations. 

 It must be sometliing very new to raise wcnider in a population so 

 trained. The exhibitions' of the Society of Arts begin to pall, and 

 tlie prosecution of the great undertaking will alone preserve their 

 reputation. 



Tlie results to be expected from an exhibition here must be very 

 difl^erent from those on the continent. ^Ve do not want to glorify 

 manufacturers, to teach governments or people the value of the 

 manufacturing arts; we cannot do much in saimulating tlie enter- 

 prise of our population, for they are figliting against the world. 

 Much of the result will be owing to claptrap. The exhibition, in 

 the Queen's name, in Hyde Park will be a show and a holiday, and 

 tens of thousands in London and throughout England will pay 

 their shillings, regardless of anything but getting pastime for it. 

 Still, some good may be done. Our progress in many branches of 

 manufacture may be made visible, and this will be an encourage- 

 ment for future exertion; our shortcomings in some may be made 

 known, and English enterprise may be drawn into fresh channels. 

 We must not, however, be unmindful of the inherent vices of such 

 exhibitions, — the prominence given to exceptional skill, — the want 

 of relation between the artistical and meclianical results. On such 

 occasions, we see knives with a hundred blades, wliich are of no 

 possible use, and a whole table- service within a walnut-shell; cast- 

 ings to rival those of Prussia; silks those of Lyons; — but, after all, 

 a better criterion of national skill than any Exposition, is the 

 £,. s. d. return of the Board of Trade. From the first Exposition 

 in Paris, there perhaps has not been one in which the wares of 

 "perfidious Albion" have not been beaten; there has never been an 

 exhibition in a colony, but the prizeholder has produced goods 

 equal to those of the mother country: but the commercial results 

 remain unaltered. To make a good article is one essential, but to 

 make a cheap one is another; and the most successful manufac- 

 turer is he who does the latter, and as much enterprise must be 

 exerted to effect this, — so after all the cheapest manufacturer is 

 commonly the best. He who can substitute a machine for handi- 

 work, not only obtains greater economy, but greater pi-ecision. 



At this present time it is not possible to predict results. The 

 organization of local committees does not require any special su- 

 pervision, hut hereafter it will become of the greatest importance 

 to provide properly for the suitable working of the undertaking; 

 and unless it be chiefly by the manufacturers themselves, we are 

 convinced it will fail. If, too, there is to be a centre of toadyism, 

 flunkeyism, and jobbery, the fate of the plan will be sealed. Prince 

 Albert has done his part in launching the undertaking, — he may 

 use his influence witli the government in obtaining grants of money 

 and land: hut interference in the details must he fatal. When the 

 Prince is present, the freedom of discussion will be swamped by 

 conventionality; when absent, his delegate will rule for him, and 

 he will be compromised unwittingly. The Prince's name will he 

 used in every kind of way, as it has been freely used in giving his 

 name to the plan; and instead of Mr. Whishaw, Mr. Cole, or Mr. 

 Scott Kussell being responsible for his own suggci^tions, he will arm 

 himself with the authority of the Prince. Therefore we say, let 

 tlie committees at once take upon themselves the necessary autlio- 

 rityand responsibility: do not let them fear to displease the Prince 

 by meddling with his plan or his arrangements; but rather to strive 

 for what will truly please the Prince — that is, to carry out the 

 great enterprise in which he has embarked with them. 



Let there be no want of zeal on this occasion, but, as it is deter- 

 mined to have an exhibition, let it be one of which England need 

 not be ashamed, and which shall surpass all which has been before. 

 This we can do, and therefore we ought to do it; and the only way 

 is to go heart and hand to the work, — not caring whether a prize 

 fund be raised or not, or whether the prizes are or are not fairly 

 dealt out to each branch of manufacturing industry. 



EXPANSION OF LIQUIDS. 



On a Formula for Culfulutiny the E.vpanaion of Liquids by Ileiit. 

 By W. J. Macquokn Kankink, C.E. — [From the Edinburgh New 

 PhitoxojMcal Journal for October, 1819.] 



Having been lately much engaged in researches involving the 

 comparative volumes of li(piids at various temperatures, I have 

 found the following formula very useful: — 



Log V = B< -H - — A. 



Log V represents the common logarithm of the volume of a 

 given mass of li(|uid, as compared with its volume at a certain 

 standard temperature, whicli, for water, is the temperature of its 

 maximum density, or 4°'l centigrade, and for other liquids 0° cen- 

 tigrade. 



t is the temperature measured from the absolute zero mentioned 

 in my paper on the 'Elasticity of Vapours,' in the Edinburgh IVeu) 

 Philosophical Journal for July 1849, and is found by adding 274°-6 

 to the temperature according to the centrigrade scale. 



A, B, and C, are three constants, depending on the nature of the 

 liquid, whose values fur the centigrade scale, corresponding to 

 water, mercury, alcohol, and sulphuret of carbon, are given below. 



A. Log B. Log c. 



Water 0-44141107 4'-8US;.')4S 1-78'J0285 



Mercury 0l'22in3ll 5a04S7(iti i-a70:i«97 



Alrohol 0-2'il5i33 484144.'i2 1-28<JS05I> 



Sulphuret of Carbon 0-2.M0074 4-B483-I72 1-21'.I2054 



The data from which the constants have been computed have 

 been taken from the following authorities: — for water, from the 

 experiments of Ilallstriim; for mercury, from those of Regnault; 

 and for alcohol and sulphuret of carbon, from those of Gay-Lussac. 

 As the experiments of M. Gay-Lussac give only the apparent ex- 

 pansion of the liquids in glass, I have assumed, in order to calcu- 

 late the true expansion, that the dilatation of the glass used by 

 him was -0000258 of its volume for each centigrade degree. This 

 is very nearly the mean dilatation of the different kinds of glass. 

 M. Regnault has shown that, according to the composition and 

 treatment of glass, the coefficient varies between the limits '000022 

 and -000028. 



Annexed are given tables of comparison between the results of 

 the formula and those of experiment. The data from which the 

 constants were calculated are marked with asterisks. 



The table for water shows, that between 0° and 30° centigrade, 

 the formula agi-ees very closely with the experiments of Hallstrom, 

 and that from 30° to 100° its results lie between those of the 

 experiments of Gay-Lussac and Deluc. 



The experiments of Gay-Lussac originally gave the apparent 

 volume of water in glass, as compared with that at 100°. They 

 have been reduced to the unit of minimum volume by means of 

 Ilallstriim's value of the expansion between 4.°-l and 30°, and the 

 coefficient of expansion of glass already mentioned. 



In the fifth column of the table of comparison for mercury it is 

 stated which of the experimental results were taken from M. Reg- 

 nault's own measurements on the curve, representing the mean 

 results of his experiments, and which from his tables of actual 

 experiments, distinguishing the series. 



In the experimental results for alcohol and sulphuret of carbon, 

 the respective units of volume are the volumes of those liquids at 

 their boiling points, and the volumes given by the formula have 

 been reduced to the same units. 



Expansion of Water. 



