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THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



[October 



second, it would tend to make him turn round on himself. If, then, you 

 were inviuiably to iittaeh the barrel in a horizontal position, to a moveable 

 vertical axis, at the moment of the explosion it would change its direc- 

 tion, more or less, and would cause this axis to turn. 



Preserving the same disposition, let us suppose, that the vertical 

 rotary axis be hollow, but closed at its upper part; that it abut below, 

 like a chimney upon a cauldron, in which steam is generated ; that, more- 

 over, there exist a free lateral communication between the interior of 

 this axis and the interior of the gun barrel, so that, after having filled 

 the axis, the steam penetrates into the barrel, and goes out through its 

 side, by a horizontal opening. Except in intensity, this steam, in its 

 escape, will act in the same manner as the gas disengaged from the 

 powder would act in a gunbarrel, stopped at its mouth, and pierced 

 laterally, but, here, we shall not have a simple shock, as happened in the 

 case of the sharp and instantaneous explosion of the gun ; on the con- 

 trary, the rotary motion will be uniform and constant, like ihe cause by 

 which it is generated. 



If we take, instead of a single gun, or rather a single horizontal tube, 

 a vertical rotary tube, we shall have, with some slight differences, the 

 ingenious work of Hero, of Ale.xandria. This is, without any fear of 

 contradiction, a macliine in which the steam of water engenders mo- 

 tion, and might produce mechanical effects of some importance— in fact, 

 a genuine steam engine. Let us, however, not fail to remember that 

 neither by form, nor by the mode of action of motive power, has it any 

 resemblance to the machines of that kind now in use. If ever the re- 

 action of a current of steam should be rendered useful in practice, 

 we must incontestably award the originality of the suggestion to Hero;* 

 but at the present day the rotatory eolipile can only be cited here in the 

 same manner as engraving on wood is referred to in the history of 

 printing, t 



In the machines used in our factories, in steam packets, and on rail- 

 ways, motion is the immediate result of the elasticity of steam ; it is, 

 therefore, worth while to inquire liow and where the idea of this power 

 originated. The Greeks and Romans were certainly not unaware that the 

 steam of water could acquire a prodigious mechanical power, and they 

 explained, eveii at that time, by the sudden vaporization of a large mass 

 of this liquid, the fearful earthquakes which, in a few seconds drove the 

 Ocean from beyond its natural limits ; scourges which, at one fell blow, 

 sweep from their foundations the strongest monuments of human indus- 

 try, which raise dangerous shoals in the soundless depths ol the ocean, 

 and raise up lofty mountains even in the middle of continents. What- 

 ever may be said, this theory of earthquakes does not necessarily suppose 

 that its authors had gone into investigations, expcrinienis, and precise 

 calcutations. No one is now ignorant that at the time when heated metal 

 is admitted into the earthen or plaster moulds of the founder, that a few 

 drops of moisture, concealed in these moulds, are sufficient to cause a dan- 

 gerous explosion. Notwithstanding the progres_s of science, our modern 

 founders have not been always successful in pre'venting these accidents; 

 how then could the ancients have provided against them ? While they 

 cast the moulds of statues, the splendid ornaments of their temples, 

 public places and gardens, and of the private habitations of Athens, and 

 ot Home, some accident must necessarily have happened ; the men of art 

 found out the immediate cause ; the philosophers, on the other hand, 

 carrying out the spirit of generalization, which was the characteristic tiait 

 ot their schools, saw in these instances, genuine types of the eruptions 

 of Etna. 



All this may be very true, without having much relation to the subject 

 with which we are engaged, and 1 have not, I own, dwelt so much as I 

 might have done upon such slight lineaments of the ancient science re- 

 lative to the power of steam, desirous, if I could, of remaining in peace 

 with the Daciers of both sexes, with the Du:ens ot the age.{ 



Natural or artificial powers before they become truly useful to man, have 

 nearly always been pressed into the service of superstition, and steam 

 forms no exception to the general rule. The chionicles inform us, that 

 on the banks of the VVeser, the god of the ancient Teutons sometimes 

 e.vpres.-ed his displeasure, by a sort of thunderclap, which was immedi- 



• It 13 a remarkable fict, of which M. Arago appears nol to be aware, tljat Hero's 

 simple engine of emission is at this moment in use, bolli in this connu j and in 

 America. Wc know of one sleara-cngine of Hero's of IwenCy-one horses' power, and 

 us only fault is tlie consuming too much steam and fuel. It is, oUierwise, a simple, 

 cheap, and efleclive steam-engine. -Note of the Atheuxuni. 



f These remarks also apply to a plan publijlied at Rome, in 1029, by Branca, an 

 Italian architect, in a work entitled. La Macchiiia, and which was to engender a ro- 

 tatory moveineut, by directing llie steam issuing from an eolipile, under the form of 

 • bel owsora blasi of wind, upon the floats of a wheel. If, coiurary to piob.ihilily, steam 

 should one day be employed, usefully, as a direct blast, Branca, or the unknown 

 author, Iruin whom he might have borrowed Oiis idea, will take a fiistiate position 

 in the history ot Uus new kind of machine; but, with regard to the present machine, 

 Branca s claims are absolutely null,— A^o^e n/M. Arayo. 



J For the same reason, I cannot refrain from relating here an anecdote, which, 

 with a spice 01 romance and par.idox comparison, as lo what we now know of the 

 action ot steam, gives us a g unpse of the importance which the ancients attached to 

 Ihe power ot this mechanical aput. It is iel;,ted ih.it Anthemius, the architect, em- 

 ployed by Justinian in the buiMiug of St. Sophia, had a bouse near that of Zeno, 

 an.l that to annoy this orator, his open enem,, l,e placed on the ground Hoor of bis 

 own house seveial cauldrons full ot water. From h^les cut in ibe lids of each of 

 hese cauldrons, he ea.ried a flexible tube, which was applied to the p..rty-wall 

 under the beams which supported the flooring of Zeno's house; and that, as soon as 

 the hie was lighted under the cauldrons, he made the doors daucc as if they bad 

 been atlected by an cartliquake.— .\'ofe by JI. Jmja. 



ately succeeded by a cloud, filling the whtde edifice. The image of the 

 god, Busterich. found it is said, in antiquarian researches, fully reveals 

 the manner in which the pretended miracle was worked. The god was, 

 metal, and the hollow head enclosed an amphora of water ; wooden 

 stoppers shut up the month and another hole situated above the fore- 

 head. Coals were adroitly introduced into a cavity of the skull and gra- 

 dually heated the liquid; the steam engendered, soon drove out the 

 stoppers, with a loud noise, and then rushed out, in two jets, forming a 

 dense cloud between the god and his stujiid worshippers. It seems, also, 

 that during the middle ages the monks made the invention tell, and that 

 the head of BustL-rich did not perforin only before heathen assemblies.* 



The next step, by which we reach any useful ideas on the properties 

 of steam, after the first glimpses of the Greek philosophers, is by an in- 

 terval of twenty centuries. It is true, however, that then experiment.s 

 exact, conclusive, and irresistible succeed conjectures, unsupported by 

 any tangible proof. In 16U3, Flurence Rivault, gentleman of the 

 chamber to Henry 1st., and tutor to Louis XII!., discovered, for instance, 

 that a bomb of thick metal, and containing water, explodes sooner or 

 later, on being placed on the fire, after being stoppered ; that is to say, 

 when the steam is prevented from freely expanding in the air, in propor- 

 tion as it is formed. The power of steam is here characterised by a 

 proof, clear, and susceptible to a certain point of numerical appreciation,! 

 but it presents itself still farther to us as a terrible instrument of de- 

 struction. 



Able minds did not stop at this miserable conclusion, they perceived 

 that mechanical powers must become, like human passions, useful or in- 

 jurious, precisely as they are well or ill directed. In the case of steam 

 only, the commonest skill was really necessary to apply lo productive 

 labour, the terrible elastic power, which, according to all appearances , 

 shakes the earth to its touiitlations, surtouiids the art ot the statuary with 

 imminent dangers, and bursts into a thousand pieces the thick metal of 

 the bomb. In what state is this projectile found before its explosion ? 

 The bottom contains very hot water, iut still liquid; the rest of its 

 interior is full of steam ; this, for it is the characteristic mark of gaseous 

 bodies, exercises its power equally on ail sides, and presses with Ihe 

 same intensity on the water, and on the metal walls which relain it. 

 Let us place a cock at the lowest part of the metal ; when it is opened, 

 the water, pressed by the steam, will spout out with extreme velocity. 

 If the cock ends in the pipe, which, after having been bent outside around 

 the bomb, is tiu-ned vertically from the bottom ujiwards, the water 

 driven back will ascend it so much the more, as the steam has more elas- 

 ticity; or rather, for it is the same thing in other words, the water will 

 raise itself so much the more, as its temperature becomes higher ; this 

 ascending movement will only be limited by the resistance of the walls 

 of the machine. For our bomb, let us substitute a thick metallic boiler, 

 of large capacity, and nothing will prevent us Irom carrying great masses 

 of the liquid to indefinite heights, by the simple action ot steam; and 

 we shall have created, in every meaning of the word, a steam-engine for 

 draining. 



You now know the invention which France and England have dis- 

 puted, like formerly, seven cities of Greece contended, in turn, for the 

 honor of giving birth to the immortal Homer. On the other side of the 

 channel, the .Marquis of Worcester, of the illustrious house ot .Somerset, 

 is universally recognized ; this side of the strait, however, we contend 

 that it belongs lo an humble mechanic, almost totally forgotten by bio- 

 graphers, Solomon de Cans, who was born at Dieppe, or in its iieigh- 

 bourhootl. Let us examine impartially the claims of the two competitors. 



* Hero, of Alexandria, atti ibuled the soauds, proceeding from the statue of Meinnon, 

 when the rays of the sun fell on it. and which excited so much contioversj, to the 

 passage by certain openings of a current of steam, which the solar heat produced, at 

 the expense of the luiuid.wilh whicli the Egyptian priests are said to have furnished 

 the interior of the pedestal of the colossus. Solomon de Caus, Kircher, and others, 

 have endeavoured to liiid out the particular means by which the llieociatic fraud was 

 thus made to operate upon credulous iinaginatiuiis, but every thing induces us to 

 believe that they have not hit upon the right cause, if on this subject any thing were 

 to be guessed at all.— A'ofe by M. .'Jiayo. 



t If any learned personage should discover that I have not gone far enough back, by 

 begiuning with Flurence Rivault; if he should point out tome a quotation from 

 Albeili, who wrote in 1411 ; and if, Irom this author, he atbrined that in the com- 

 raenceiiient of thefifteeiilh, century the lime-burneis feared extremely for ihemselves 

 and llieir ovens, the explosions of lime-stones, in whi^b there might chance lo be some 

 cavity, 1 should replv,tliat Alberti was iiot himself aware of the true cause of these 

 explosions, but attributed them to the transformation into steam of the air contaiueti 

 in the cavity, acted upon by the Hames; and I should observe, that a bit of lime- 

 stone, accidently hollow, would not have given any of those means of numerical, 

 appieciatious whicli seem to be pieseiited by RivauU's experiments. — JSote by M, 

 Arayo. 



In the first era, many of the experiments of steam were known and tlioioughly un- 

 derstood. Steam was included, as it is by modern writers, under the head of the airs 

 or gases, and was said to consist of water turned into air by heat. This has misled 

 M. Arago, for, being apparently acquainted with the \\orks of the Greek philoso- 

 phers only through the ineflium of translations, he seems to imagine that when they 

 speak of air producing a given elfect, they mean only atmosplnric air, whereas they 

 fully explain themselves to mean waler turned into air, using the word generically, 

 not specifically, just as we should say water converted by heat into the gas or 

 vapour, commonly called, steam. Therefore, he infers, that the> were ignorant of the 

 principle of generating steam from waler for their peculiar purposes, and asserts that 

 the ettects mentioned a're attributable only to the gaseous mailer of our atmosphere — 

 whereas. Hero, of Alexandria, more than a century before the Christian era, under- 

 stood the subject of the generation of steim from water by heat, and its application to 

 true machinery, philosophical toys, or worse, engines devoted to the service of aujies. 

 slitiun and. idolatry .—A'o(e of the Athenxum. 



