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Hans de Laet in 1624 commenced the publica- burg, 1829), and Statistique générale, méthotion in Holland by the Elzevirs of his “Re- dique et complète de la France (4 vols. 8vo., publics,” a series of statistical works, and was Paris, 1842–6); Maurice Block, Statistique de followed during the 17th century by Conring, la France (2 vols. 8vo., Paris, 1860); J. R. Bose, Beckmann, and Gastel in Germany, by McCulloch, the author of many statistical De Luca and Everard Otto in Holland, and by works in English of great value; John McOldenburg in Switzerland, whose Thesaurus Gregor, "Commercial Statistics" (5 vols. 8vo., Rerumpublicarum (4 vols. 8vo., Geneva, 1675) London, 1848–50), and other works; the Rev. was an excellent compilation of statistical mat- John Clay, author of several works on prison ters. In 1749 Gottfried Achenwall delivered lec- statistics; Léon Faucher, author of numerous tures on statistics in the university of Götting- statistical contributions to the Journal des en, and gave the name (Ger. Staat, state) to the économistes; W. Newmarch, editor of the science. Conring, it is stated, had lectured on “ Journal of the Statistical Society;" and in the subject nearly a century before; but Ach- the United States, T. Pitkin, A. Seybert, J. S. enwall systematized it, and prepared a treatise Fisher, J. D. B. Dé Bow, Freeman Hunt, Dr. J. for the use of the students of the university Thomas, Dr. J. Chickering, T. P. Kettell

, J. S. (Staatsverfassung der Europäischen Reiche im Homans, J. O.G. Kennedy, Dr. J. G. Cogswell, Grundrisse), which passed through 7 editions and Dr. Edward Jarvis.—Within a few years in the next 50 years. Walch and Reinhard past, societies for the collection of statistics have also published text books on the subject, soon been established in most of the countries of after, for their respective universities. A stu- Christendom. The statistical society of London dent of Achenwall

, Professor Schlözer, devel- was founded in 1834, and has since 1837 publishoped the science more fully than his teacher, ed a quarterly journal. The Parisian society but died before his great work, “Theory of commenced in 1842 the publication of a monthly Statistics”. (Göttingen, 1804), was completed. periodical, the Journal des économistes, which In England, the first statistical work of note has a deservedly high reputation. In the Uniwas by Smollett, who published "The Present ted States there is a genealogical and statistical State of all Nations(8 vols. 8vo., London, society at Boston, which published for some 1768). Gatterer (Göttingen, 1773), Niemann years a quarterly “Register;" a geographical (Altona, 1807), and Leopold Krug (Berlin, and statistical society at New York, which is1807) have written able works on the science. sues a quarterly “Bulletin;" and several periLuden (Göttingen, 1812 and 1817) has been one odicals devoted in part to special statistics, such of its most

Among the as the “ American Journal of Science and Arts," statistical writers of the present century, those the “ American Journal of Education,” the who occupy the first rank are Melchior Gioja, “Merchants' Magazine,” the "Bankers Magathe author of Nuovo prospetto delle scienze zine,” “De Bow's Commercial Review," the economiche (6 vols. 4to., Milan, 1815–19) and “Mining Magazine,” and the “United States Filosofia della statistica (2 vols. 4to.); Hassel, Insurance Gazette and Magazine.” The BritLehrbuch der Statistik der Europäischen Staaten ish association for the advancement of science (4 vols., Weimar, 1812–’18), and several other has had a statistical section since 1833; the geographical and statistical works; Stein, American association has a similar section; and Manuel de géographie et de statistique (3 vols. the encouragement of the collectors of statis8vo., Leipsic, 1833); Schubert, professor at tical matters is one of the avowed means by Königsberg, Staatenkunde von Europa (6 vols., which the Smithsonian institution proposes to Königsberg, 1835–45); Meusel, Literatur der diffuse knowledge among men. Statistik 2 vols., Leipsic, 1806-17); Malchus, STATIUS, CÆCILIUS. See CÆCILIUS STATIUS. Statistik der Staatskunde (Stuttgart, 1826); STATIUS, PUBLIUS PAPINIUS, a Roman poet Schnabel, a Bohemian writer, Statistique géné- of the time of Domitian, whose birth has been rale des états Européens (2 vols. 8vo., Prague, placed in A. D. 61, and death in A. D. 96, 1829);

Herbin and Peuchet, Statistique de la though there is only uncertain evidence for France (7 vols., Paris, 1803); Adriano Balbi, either statement. His father was a preceptor various comparative statistical works on Por- of Domitian, by whom the son was patronized. tugal, France, Russia, the British empire, &c. In the Alban contests he 3 times gained the (Paris, 1822-'9); Berghaus, author of Allge- victory. Juvenal is the only ancient author meine Länder- und Völkerkunde, of Staaten- who mentions him (Satire vii. 82). It has kunde, and numerous other works, and editor been stated, but without good evidence, that of Annalen der Erd-, Völker- und Staaten- he was a Christian, and that the emperor kunde (1830–43), Geographisches Jahrbuch, stabbed him with a stilus in a moment of and other periodicals; Becker, author of nu- anger. His extant works are: Silvarum Libri merous works on Austrian statistics; Die- V., a collection of 32 poems on passing events, terici, chiefly on the statistics of Prussia and divided into 5 books; Thebaidos Libri XII., the Zollverein; Charles Dupin, Forces pro- an epic poem, founded upon the legendary acductives et commerciales de la France (2 vols. count of the expedition of the Seven against 4to., Paris, 1832), and other works; J. H. Thebes, of which the 1st book was translated Schnitzler, Essai d'une statistique générale de into English by Pope; and Achilleidos Libri l'empire de Russie (Strasbourg and St. Peters- II., an epic poem never finished. There are no good editions of Statius, the best being that was a rationalist, but he gradually inclined to found in Lemaire's series of Latin classics (4 supernaturalism. His works are very numervols. 8vo., Paris, 1825–'30). Five books of

Five books of ous, and extend over nearly every department the “ Thebaid” have been translated into Eng- of theology; but those on church history are lish by Thomas Stephens (8vo., London, 1648), the most valued. Among them are: Kirchliche and the entire poem by W. L. Lewis (2 vols. Geographie und Statistik (2 vols., Tübingen, 8vo., Oxford, 1767 and 1773). The “ Achil- 1804), the first scientific work on this subject; leid” has been translated by Howard (8vo., and Geschichte der theologischen Wissenschaften London, 1660).

(2 vols., Göttingen, 1810–’11). He was also STATUARY. See SCULPTURE.

the editor of several theological journals. STATUTE OF FRAUDS. See FRAUDS, STAUGHTON, WILLIAM, D.D., an American STATUTE OF.

clergyman, born in Coventry, Warwickshire, STATUTES OF LIMITATION. See LIMITA- England, Jan. 4, 1770, died in Washington, TION, STATUTES OF.

D. C., Dec. 12, 1829. At the age of 17 he STAUDENMAIER, FRANZ ANTON, a Ger- published a small volume of “ Juvenile Poems," man theologian and philosopher, born at Danz- and soon afterward entered the Bristol Baptist dorf, Würtemberg, Sept. 11, 1800, died in Frei- seminary to prepare for the ministry. He emiburg, Baden, Jan. 19, 1856. He studied at the grated to South Carolina in 1793, and preached university of Tübingen, and was ordained a for nearly 17 months at Georgetown, S. C. In Roman Catholic priest' in 1827. In 1828 he 1795 he removed to New York, and in 1797 was appointed tutor in the theological semi- took charge of an academy at Bordentown, N. nary at Tübingen, in 1830 ordinary professor of J., and was ordained. Toward the close of theology in the newly created theological fac- 1798 he removed to Burlington, N. J., and in ulty of the university of Giessen, in 1837 ordi- 1805 became pastor of the first Baptist church nary professor in the university of Freiburg, of Philadelphia, which increased so much unand in 1843 also a canon of the cathedral der his ministry that its house of worship was church of that city. In 1851 he was elected a several times enlarged, and three new churches member of the first chamber of the legislature were formed from it. With the last of these, of Baden. His first work was a “ History of the Sansom street church, Dr. Staughton identhe Election of Bishops” (Geschichte der Bi- tified himself, and continued there till 1823, schofswahlen, Tübingen, 1830), with particular preaching from 3 to 4 times every Sunday to reference to the rights claimed by Christian audiences of several thousands, and 2 or 3 princes. His Encyklopädie der theologischen times during the week, and at the same time Wissenschaften (Mentz, 1834; 2d ed., 1840) is instructing 15 or 20 young men in theology, the only German work of the kind in Catholic lecturing on botany, chemistry, and sacred and literature. His work on the “Spirit of Chris- profane history in two female seminaries, edittianity” (Der Geist des Christenthums, Mentz, ing wholly or in part two religious periodicals, 1835; 5th ed., 1855) has had a very extensive and presiding or assisting at the meetings of circulation, and has been translated into sever- numerous benevolent societies. In the autumn al foreign languages. The most important of of 1823 he became president of Columbian colhis works is that on “Systematic Theology” lege at Washington, D. C., which position he (Die christliche Dogmatik, 4 vols., 1844–52; not resigned in 1827, in consequence of the embarcomplete), in which he attempts to harmonize rassments of the college, which he had made the results of modern philosophy with the doc- extraordinary efforts to remove.

He then retrines of the Catholic church. His other prin- turned to Philadelphia, and was soon afterward cipal works are: Scotus Erigena und die Wis- chosen president of the Baptist college and senschaft seiner Zeit (vol. i., Frankfort, 1840; theological institution at Georgetown, Ky., but not completed); Die Philosophie des Christen- died on his way thither. He published little thums (vol. i., Mentz, 1840;

not completed); beside his numerous contributions to religious Darstellung und Kritik des Hegel'schen Systems periodicals in prose and poetry, and 5 or 6 ser(Mentz, 1844); and Der Protestantismus in mons and orations. seinem Wesen und seiner Entwickelung (Frei- STAUNTON, a river in the S. part of Virburg, 1846). Staudenmaier has also been a ginia, rising in Montgomery co., among the contributor to journals of Catholic theology, Alleghany mountains, flowing E. and S. E. and to the Protestant “Journal for Philosophy through a pass in the Blue ridge, and with and Speculative Theology," edited by Fichte. Dan river forming the Roanoke at Clarksville,

STÄUDLIN, KARL FRIEDRICH, à German Mecklenburg co. It is 200 m. long, and in the theologian, born in Stuttgart, July 25, 1761, first 20 m. of its course has a fall of 1,000 feet. died in Göttingen, July 5, 1826. He studied STAUNTON, a town and the capital of Autheology and philosophy at the university of gusta co., Va., situated on a small tributary of Tübingen, from 1786 to 1790 made several lit- the Shenandoah river, 120 m. W. N. W. from erary journeys through Germany, Switzerland, Richmond; pop. in 1850, 2,500; in 1860, France, and England, and was appointed in 14,124. It is the oldest town in the valley of 1790 professor of theology at the university of Virginia, having been incorporated in 1749, Göttingen, where in 1803 he was also made and is the seat of the western lunatic asylum consistorial councillor. In his earlier years he and of the Virginia institution for the deaf and

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dumb and the blind. It has 2 weekly news- approved of the theses of Luther against the papers, 10 or 12 churches, several banks and papal indulgences, though he did not publicly banking houses, 2 academies, and 2 seminaries. declare himself in favor of them. In 1518 he It is surrounded by a populous and rich agri- was with Luther at an assembly of his order at cultural region, and has an important local Heidelberg, and in the same year demanded at trade. There are mills, founderies, and manu- Augsburg that Luther should not be condemnfactories of various kinds. The Virginia cen- ed unheard and untried. Soon after, however, tral railroad passes through it, and it is the fearing an adverse issue of the controversy, he proposed terminus of the Manassas Gap rail- withdrew to Saltzburg, where he became court road, partially completed.

preacher, and in 1522 abbot of a Benedictine STAUNTON, SIR GEORGE LEONARD, an Eng- convent. Whether, as some assert, he was lish diplomatist, born in Galway, Ireland, April shortly before his death bishop of Chiemsee, is 19, 1737, died in London, Jan. 14, 1801. He doubtful. He is the author of two works, De studied medicine and became a contributor Amore Dei and De Fide Christiana, in which to literary periodicals, and an intimate ac- a mystic tendency prevails. quaintance of Dr. Johnson. He afterward STEALING. See LARCENY. held official position and practised medicine in STEAM, the name applied generically to the the West Indies for several years. In 1774 he vapor or non-permanent gas given off by any was attorney-general of Grenada, and when liquid, in consequence of the volatility of such that island was taken by the French in 1779, liquid and the influence of heat upon it; and he and Lord Macartney, the governor, were more especially when the vaporization takes made prisoners, but were soon released and re- place at temperatures at or above the boiling turned to England. In 1781 he went as confi- point of the substance so affected. In the redential secretary of Lord Macartney to Madras. cent progress of mechanical art and science, He made an advantageous treaty with Tippoo however, this term has come to designate in å Sultan in 1784, for which he was raised to a specific sense the vapor of water, as applied or baronetcy and received an annuity of £500 applicable to the performance of work, or to from the East India company.

He was a

other mechanical or economic purposes. In member of Lord Macartney's embassy to connection with this subject see BOILING POINT, China in 1792, of which he published an ac- EVAPORATION, HEAT, and PNEUMATICS. In popcount (2 vols. 4to., 1797).—SIR GEORGE THOMAS, ular language, the visible mist forming when a an English author, son of the preceding, vapor is discharged into the air, as a little way born in Salisbury, May 26, 1781, died in Lon- from the spout of a boiling kettle, or in a dense don, Aug. 10, 1859. He accompanied his fa- cloud above an engine “ blowing off” steam, is ther to China in 1792, entered the university also called steam. This visible mist is, howof Cambridge on his return to England, and in ever, really of the nature of cloud; being prob1799 went to Canton as secretary of the East ably a collection in immense numbers of minute India company's factory there, of which he af- vesicles formed of water condensed from the terward became president. In 1816 he was vapor, and also enclosing vapor or air, and attached to Lord Amherst's embassy to China, which, disseminated in the atmosphere, conand from 1818 to 1852, with a few intermis- stitute an opaque and visible mass, in the same sions, was a member of parliament. His prin- way as do the fine globules of a transparent oil cipal works are: " The Penal Code of the when the latter is beaten up and mingled through Chinese Empire” (4to., London, 1810); “Nar- water. Steam, properly so called, is perfectly rative of the Chinese Embassy to the Tar- transparent and colorless, as are the greater tar Khan Tourgouth during the Years 1812- number of gases of all sorts; and hence it is al'15" (1821); and “Miscellaneous Notices rela- ways wholly invisible. Whenever a confined tive to China and the British Commercial In- body or other volume of steam seems to become tercourse with that Country” (1822). A trea- visible, the truth is that a portion of the vapor was the means of introducing its practice in haze or cloud; and though there may also be some parts of the empire. He edited the steam occupying the space through which this is “History of the Great and Mighty Kingdom diffused, it is the water or cloud only that is seen. of China,” translated from the Spanish of Men- The engineer and the general reader have thus doza by Parke in 1588 (Hakluyt society, Lon- alike to bear in mind that, in dealing with don, 1853).

steam (proper), they have to do with a gaseous STAUPITZ, JOHANN VON, the friend and body which eludes the sight as completely as patron of Luther, born at Meissen, died in 1524. the purest atmospheric air. Perfect steam is, He entered in early life the Augustinian order, moreover, in no way moist, but is dry, as are obtained from the pope in 1501 general privileges the permanent gases; the moisture sometimes for the newly established university at Witten- showing upon a solid surface it touches, or that berg, and in 1508 by his influence caused Luther, has been plunged into it, being due to condena member of his order, to be called to one of sation. With such slight exceptions as are

he professorships. Luther gratefully acknowl- hereafter to be noted, steam has in a complete edges that in his spiritual struggles he found in degree those properties of fluidity, mobility, Staupitz a kind adviser and guide. Staupitz elasticity, and equality of pressure in every

or in a

MATIOS.

direction about any point in a volume of it at formed would have a feebler elastic tension, rest, that distinguish the gases; and in conse- and would be less dense; so that a larger vacuquence of which it is brought under the ordina- ous space must be continually provided as we ry laws of pressure, equilibrium, and movement approach 32°, to insure the rapid and complete of gaseous fluids, as given in the article PNEU- volatilizing of the liquid. But if into the vacu

At the same time, the rapidity with um some air were introduced, and the experiwhich, at a given condition and temperature, it ment repeated, the vaporization of the liquid can be condensed, or again formed, and the would be retarded, and more-finally even to great disturbances in its heat and elastic force nearly preventing it altogether as the density or pressure that occur at the moments of such and pressure of the admitted air were increased. changes, strikingly distinguish it from the per- This repressive effect of the incumbent air, manent gases, and in fact impart to it its pecu- however, could always be overcome by artifiliar fitness as a medium through which to ap- cially applying a sufficient degree of heat to ply the motive power of heat.--It will be re- the liquid. And when the atmospheric presmembered that the agency we call heat exists sure equalled its average at the sea level, 14.7 free in all bodies upon and about our globe; and lbs. avoirdupois to the square inch of surface, that, whenever in any body or space an excess if heat sufficient could be supplied, any quantiof this free heat is in any way caused to appear, ty whatever of water would still vaporize and as by combustion of wood or coal, or the action become steam instantly, against and in spite of the sun's rays, this excess at once tends to of such pressure, at the moment when the tembe imparted to and equalized throughout sur- perature of the entire liquid mass became raised rounding bodies and spaces, at such rates as to 212°. Thus, while evaporation takes place the nature of the latter, their surfaces, &c., will slowly at all temperatures, down to and below allow; while, if at any place a reduction of zero of Fahrenheit, giving vapor of feebler tenheat occurs, the surrounding bodies and spaces sion and less density—the tension at 0° equalimpart heat to this, and again with a rapidityling is inch of mercury-a vaporization of whole depending on their nature and the character volumes of liquid (larger or smaller, according of the surfaces separating or bounding them. to the facility with which the requisite heat Now, between the particles of all fluids there can be supplied to enter into the latent form, is acting at all times a repulsive force or ener- or give to the resulting vapor its tension) must gy, greater or less, tending to drive the parti- commence in any body of water or other liquid cles asunder; if the body be a liquid, to throw so soon as the tension of its vapor is made it into the gaseous condition; if a gas, to en- equal to the pressure of air or other gaseous large still further its volume. It is this repul- bodies upon the surface of the liquid. It is sive energy that, as we pump off the surround- this tumultuous vaporization that we call boiling atmosphere from about a tight bladder ing; its rate being really slow, and the process holding a little air and placed in the receiver of prolonged, only (and fortunately, in view of an air pump, goes on distending the bladder, till the risk otherwise of continual explosions) by it may even burst it from within outward. The reason of the fact that but a limited and gradrepulsive action in these bodies is moreover ual supply of heat can, under any circumstances, known to be either directly that of heat, or be made to enter the liquid. The principal such as heat directly conspires with and aug- fact here, and the one never to be lost sight ments. And as the small body of air confined of, is, that any liquid in ordinary conditions in the bladder is, in the atmosphere, kept by vaporizes in volumes, i. e., boils, at the precise pressure of the surrounding air within a mod- moment when the tension of its vapor due to erate volume, so it is found also that a vast num- heat has risen to an equality with the pressure ber of liquids—those termed volatile—at any of that atmosphere, whether of common air, or ordinary temperatures owe their liquid state of confined vapor already formed, which rests to the superincumbent pressure of the atmos- or presses upon its surface. And no matter phere upon their surfaces. Water is, for all how the vapor forming is in the main enclosed, temperatures above its freezing point, a per- if there be but one small aperture in the boiler, fectly volatile liquid; so that if we should in- the cylinder, or other passages, through which troduce a pint of it, at any temperature from the atmosphere without can transmit its pres212° down to 32°, into a perfectly vacuous space sure, and any excess of vapor within above large enough to contain the resulting perfect that pressure can escape, it is still the atmosvapor, the whole of the liquid would vaporize pheric pressure precisely that acts upon the instantly and disappear in the gaseous form. liquid surface. Hence it is seen that, the charThe only other condition necessary to this re- acter of the vessel and other conditions being sult is, that the bodies in contact with the like, and the incumbent pressure the same, the liquid when introduced shall be able to yield temperature of ebullition of the liquid remains to it a sufficient amount of heat to convert it always the same; that under a given pressure as stated; this heat becoming latent in the the temperature of the liquid remains constant vapor, and the bodies parting with it becoming through the whole period of the ebullition, correspondingly cooled. In so vaporizing the a greater quantity of heat communicated to the water, also, as the temperature taken for the liquid having only the effect to evolve during change was lowered, the vapor itself when a given time a larger volume of steam; that

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the elastic force or tension of steam forming at density and pressure diminish, as in the per212° F. is precisely equal to the weight of the manent gases. If, then, the volume be again superincumbent atmosphere, or very nearly reduced, the density and pressure increase, 14.7 lbs. per square inch; and that when, by until they return to the maximum due to the confining the vapor obtained, its density and temperature, reaching the condensing point; pressure are increased, a higher temperature be- and the effect of further diminution of volume comes necessary to secure ebullition, and we say must be precipitation or liquefaction of correthat the boiling point is raised. Steam forming sponding quantities of the vapor, the density by boiling at 212° is thus said to have a tension remaining constant, and even until the whole or pressure of 1 atmosphere; at 234°, of 14 at- mass of vapor had thus been forced back to the mospheres; at 250°, 2; at 264°, 21; at 274°, 3; liquid condition. If, after all the liquid is at 292°, 4; at 306°, 5; at 340°, 8; at 357°, 10; evaporated, or a portion of it has been sepaat 389°, 15; and at 415°, 20 'atmospheres, or rated in any way from the water surface, the about 294 lbs. per square inch. Generally, as application of heat be continued, the state of produced over or in communication with water saturation is left behind; and even if the same of its own temperature at the moment of its density be preserved, the tension or pressure formation, steam is at its maximum of density is increased, though not so rapidly as if with for the temperature, whatever that may be. the same increase of temperature the steam Under such circumstances, however, the steam could remain in contact with the water, and mass owes a part of its actual density to the so continue to maintain through this rise the holding of more or less of finely divided water condition of saturation. The steam so sepaor mist in suspension through it. In whatever rated and heated loses the moisture which may its density may consist, the greatest pressure accompany it in the saturated state, and at a under which steam can exist at a given tem- few degrees of added temperature acquires in perature, as steam, is also the least pressure full the character of a perfect gas; it is then under which water similarly heated can retain said to be surcharged with heat, and it is the liquid form. This is called, for the given known as gaseous or subsaturated steam, more temperature, the pressure of saturation; and' commonly as “superheated steam,” and is by the steam is said to be saturated. On the other some writers termed "stame." Let steam in hand, steam refuses to generate freely or in vol- this condition be replaced in contact with the umes with less than this maximum quantity of water in the boiler, or in any way brought into vapor. That is, steam and water thus condi. free communication with it—the water having tioned are, so to speak, at an equipoise; increase yet the original temperature-and such steam of heat will increase the quantity of water va- would immediately evaporate and absorb a furporized, and so, in a confined space, the density ther portion of the water, transferring to this of the vapor; or increase of pressure will com- its excess of heat, and would become saturated, pel a portion of the vapor already formed to re- its temperature falling to that of the water.sume the liquid state. The steam stands, at the The relation, generally, of heat to the producsame moment, at the condensing point and at tion of mechanical effect, or work, is considered the generating point; and in fact, throughout under HEAT. The unit is the mechanical equivthe entire range of heat, there will occur at alent of the heat required to raise through 1° every point, in unalterable conjunction, one F. 1 lb. of water; and this, experiment seems density, one pressure, and one temperature; to show, is 772 lbs. weight raised against gravand always, the density being given, the other ity through 1 foot of height, i. e., 772 footelements will correspond. Of course, when pounds. If 1 lb. of water at 212° be injected change in one of these particulars occurs, slight into a vacuous space of 26.36 cubic feet-this lapses of time must be allowed the others to being the volume of 1 lb. of saturated steam adjust themselves to this; but the agreement at that temperature—and if it be evaporated of all the conditions just expressed is that to into such steam, there will be expended in the which the steam mass communicating with the process 892.9 units of heat. Now let a second water in the boiler is always tending. If pound of water at 212° be injected into and from steam under more than one atmosphere evaporated in the same space; and this, havof pressure, and the temperature and density ing to assume its volume or advance against a of which are proportionally increased, some pressure of 14.7 lbs. per square inch, will perheat be withdrawn, the tension and hence the form work to the amount of 26.36 x 144 x 14.7 density fall, and part of the steam resumes the lbs. = about 55,800 foot-pounds; and since state of water. If, while the temperature re- 55890=72.3, this quotient will be the number mains constant, the space or volume over the of additional units of heat that must in such water be increased, then, so long as there re- case be consumed or expended in displacing the mains an excess of liquid to supply fresh vapor first steam atmosphere, against which the secfor the augmented space, the density and ten- ond must advance; so that to convert the secsion will not diminish, but remain constant at ond pound of water into steam against this the maximum due to the given temperature. pressure will require 965.2 units of heat. When If, after all the liquid is evaporated, heat be steam flows from the boiler into vacuous space, not added to the steam mass, but the space or without performing work, its temperature, volume be enlarged, the steam expands, and its chiefly by reason of its friction against the

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