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having escaped all the dangers of the way, a hot-bed, of which our air is the glass. was placed one night ready for immediate From experiments of the class described, service. In the morning its surface was Herschel and, separately, Pouillet inferred found covered with a net-work of miscel- that the sun's heat is great enough to melt laneous scratches. It had suffered at the in one year a crust of ice one hundred feet hands of friendship. One of the soldiers, thick covering the entire globe-both the wishing to do a kindly deed for the pro- day and night sides. Numerous trials fessor, had gone to work in the morning have been made since then to solve this twilight with his buckskin gloves at the problem more accurately. The quantity mirror. He had polished as faithfully as of the sun's heat, or its melting power, is the ruler of the Queen's navee, and left the called in scientific jargon “the solar coninstrument with about as much capacity stant.” As has been said, this lies at the for reflection as a tin pan. The professor base of a correct science of meteorology. had, however, some unexpected reflec- The Mount Whitney observations show tions.

the sun to be hotter than was supposed. In spite of all difficulties, the experi- The heat received at the earth's surface is ments were very fully carried out. A probably more by one-half than was estimass of observations was taken on the mated by Herschel and Pouillet, and even mountain and simultaneously at its base. materially exceeds the values assigned by Some time has been spent in reducing more recent investigators. It would in these since the return to Allegheny. A one year melt a crust of ice over the whole formal scientific report to the War Depart- sunward half of the earth six hundred ment is in preparation. If addressed to feet thick. This is, of course, a statement the world of science, it might properly be in very round numbers. The scientific gin with the stereotyped phrase of mercan- phrase would be that the sun's vertical tile circulars from the East Indies: "Gen- energy could raise the temperature of one tlemen; we have the honor to confirm our gram of distilled water three degrees Cenprevious advices."

tigrade per minute for each centimeter of Sir John Herschel at the Cape of Good the earth's surface nominally exposed. Hope found that the sun's rays were hot Having supplied us with an increased enough without concentration by lens or amount of heat, the Mount Whitney exmirror to cook a family dinner. It was periments also favor us with new figures only necessary to place the raw food in an of intenser cold. The estimates of Heropen metallic vessel, put that in the Afri- schel and Pouillet made the temperature can sand exposed to sunshine, and cover of space 224° below the zero of Fahrenheit. the whole with glass after the manner of The new results carry it down nearly to a hot-bed. Certain solar rays go through the calculations for the absolute zero, the the glass almost as easily as they come absence of all heat, say minus 459° F. from the sun, but they can not so readi- To the non-scientific mind the distinction ly return till they leave some of their heat between such far-down temperatures is behind. Theirs is the predicament of the not unlike that between the pains of fox that squeezed himself into the hen- rheumatism and those of gout, the first coop, but found that he could not get out being as from a thumbscrew twisted to the without disgorging his meal. In one of last point of human endurance, the gout the experiments near the summit of Mount giving one turn more. Whitney, a copper vessel was simply cov- Further, it appears that the direct heatered with two sheets of plain window ing power of the sun can not raise a therglass, and exposed direct to the sun; the mometer quite 50° F. above its surroundtemperature within the vessel soon rose ings, whatever they may be. If we supabove boiling-point. A solar engine might pose the whole globe a thermometer, and be set to work there in the midst of a without an atmosphere, the sun could only snow-field, making its steam without fuel, heat it fifty degrees above the cold of fire, or concentrating lenses. This discov. space, leaving it at about minus 400° F. ery should be commended to the heat, under full sunshine. The internal heat light, and power companies that are tear of the earth may be disregarded in these ing up the streets of New York; they calculations. It seems paradoxical to say might be induced to transfer their opera- that if the atmosphere were removed from tions to Mount Whitney.

the earth, its surface would receive more The whole globe has been compared to heat and yet be much colder. But this is

a fact of the same kind as our experience in ascending a mountain. The atmosphere does indeed cut off a great deal of heat, but on the other hand it keeps a great deal of that which it permits to pass through. When the air is heated up to its retaining capacity an “equilibrium" is established.

To illustrate: let us imagine a large, empty, windowless hall, with two doors partially obstructed by Centennial turnstiles, one for entry and one for exit. A procession of one hundred persons enters per minute. At first there is abundant room; few want to come out. At the end of the second or third minute perhaps only three people are leaving for one hundred arriving. After a longer interval the number of departing guests is much greater. At last the hall is crowded to its utmost capacity, and if we still suppose one hundred per minute entering, it is absolutely certain that one hundred per minute must be getting out. This final condition is one which we

may call equilibrium. If the turnstiles of Centennial pattern record their turnings, we can ascertain exactly how many people are in the hall at any moment. Now to apply the illustration to heat-bearing rays entering our atmosphere, we may suppose that nearly all reach the soil through radiation; that ninety per cent. go out through the regular exit of “convection”; nine per cent. squeeze back through the turnstile by which they entered—"radiation”; and one per cent. climb out through the chimney of conduction.” It follows that by merely regulating the turnstiles, by modifying this capacity for selecting and holding rays of certain wave-lengths, atmospheres could be constructed which would keep the planet Mercury cool, or the far-off Neptune comfortably warm. Here is a hint for romancers who wish to plant their dramatis persona in some other world.

The Allegheny and Mount Whitney observations firmly establish the fact that the sun is blue. The particular shade of color which it has, if viewed without intervening atmosphere, may be laid down as that on the border of the blue near the green, about where the line F appears in the spectrum. Sad to say, this is not an “æsthetic” hue; it is more like that referred to in one of Southey's poems: “You could almost smell brimstone, their breath was so blue, for he painted the devils so well.” The sky, as seen from the summit of Mount Whitney, was of a deeper violet than had been observed elsewhere, even at Mount Ætna, in Sicily. The air was extremely dry, no mist or fog being at any time apparent.

In another set of experiments, not here described, Professor Langley determined exactly how much and what kind of heat was lost during the operation of the bolometer. The silver of the mirror, the glass, the grating, even the lampblack on the metallic

strips, each se

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lects and abstracts certain rays. Full allowance was made for these absorptions.* When the final result is presented graphically, it shows that at the earth's surface the hottest part of the spectrum is near the orange. This is quite different from previous

* The curious fact presented itself in the course of these experiments that lamp black, which is one of the most opaque substances known, is more or less transparent to some of the invisible rays.

conceptions. The diagram which makes will only believe what they see, must wait this display for the normal spectrum shows awhile for the photograph to overtake the three, curves, each somewhat irregular. bolometer. The lowest of these represents the solar This viewless energy is not a mere abenergy as we receive it, at sea-level; the straction. It is two-thirds of all that gives second, the distribution of that energy in our warmth, our weather, and our crops. regions outside our atmosphere ; 'the third, Before the observations here described the distribution at the photosphere of the were made, it was supposed that our atmossun before the solar atmosphere has inter- phere absorbed the invisible rays below vened. The similarity of these curves is the red very much, and the visible very striking. Another diagram gives the dis- little. Now the fact is found to be exactly tribution of energy in the prismatic spec- the other way. The absorption increases trum, in which the red end is abnormally in regular gradation from the red end crowded, while the blue end is unduly ex- toward the violet. tended. The curves are constructed by Important as are the observations of scale from actual and repeated measures the new astronomy up to the present time, with the bolometer, photometer, and other instruments. Deep notches in the curves, showing the decrease of energy at certain points, are found to correspond exactly with the more marked Fraunhofer lines,

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PRISMATIC SPECTRUM.

so far as they are visible. The existence they are only the beginnings of knowledge. of similar lines in the invisible part of the They will appear merely as outline sketchspectrum has been partially demonstrated es when the hand of science can complete by photography as well as by the bolom- the picture. Nothing could be conceived eter.

as more unpractical than the study of the “Groping in the dark" is a good de- stars, and yet no professed philanthropy scriptive title for the work of mapping the has been of half so much benefit to manspectrum beyond the visible rays. Much kind.

Much kind. When the Cape of Good Hope was labor is here required to measure wave- occasionally doubled by the voyagers of lengths accurately; one of them has ab- the sixteenth century, only one ship in sorbed two weeks of continuous experi- four returned to Europe in safety. Now ment. The exact relation between the not one vessel in forty is lost. The art of prismatic and the normal spectrum has guiding ships by observations on the heabeen determined. The great extension of venly bodies, and the telescopic study of the spectral field is an important result. the moon, have robbed the sea of its greatIt is as if the compass of a well-known est dangers, reduced the cost of marine inmusical instrument had been enlarged by surance, and saved hundreds of thousands additional octaves. The visible part of of human lives. The new branch of asthe spectrum is little more than an eighth tronomy promises even greater benefits, of the whole. About three times as large both by sea and land, to civilized man. a space had been somewhat known to in- Whatever of credit may accrue to the vestigators of the ultra-red region, and researches at Allegheny should be fairly has been recently photographed by Cap- apportioned alike among those who pertain Abney. The new researches of Pro- formed the work and those who gave it fessor Langley double the length of this pecuniary or official aid. Professor Langinvisible end. Doubting Thomases, who ley has been fortunate in securing and training two skilled assistants, Frank W. feet long; old style-smoked rafters, diaVery and J. E. Keeler. The latter was mond panes, etc. one of the most efficient members of the A shed, pig-sty, and two paddocks went party in Southern California. The ap- with the tenement. Rent of the lot, £11. propriation from the revenue of the Count Moore became the tenant, made boots and Rumford fund paid a part of the cost of shoes incessantly for years, and sold them constructing the first bolometers. The at Henley, Reading, or Wallingford mar. expense of special experiments with that ket. He would carry in a sackful on instrument, and the "plant" of apparatus his back, stand behind them in the marrequired, were the heaviest burden; this ket-place, and if he got rid of them, would was lifted by the liberal Pittsburgh citizen. often buy a pig or a cow, or even a pony, Some help was also given from the Bache with such excellent judgment that he alfund of the National Academy. The fa- ways made a profit; and when he bought cilities tendered by the War Department, at a fair he often sold his purchase on the and the interest taken by General Hazen road, for the nimble shilling tempted him. of the Signal Service, in addition to the One of his declared axioms was, “Quick aid already mentioned, made the Mount come and safe keep." Whitney experiments possible. The Pull- In 1849 my brother inherited the Ipsden man car of the Pennsylvania Railroad estates, and a year or two afterward occugave help and comfort.

pied an old house of his near Scott's ComServices like these are not rendered in mon, and so he became Mr. Moore's neighthe hope of reward or fame. Their future bor. He soon found out to his delight value can not be foreseen by prophet nor that this shoemaker was a character, his estimated by mathematician. But in any leading traits ostentatious parsimony, huevent they will bring to those who have morous avarice, and jolly dissatisfaction; given substantial aid science a share in his phraseology a curious mixture of rural the satisfaction that ever comes to the doers dialect and metropolitan acumen. of generous deeds.

As many of his sayings sounded like proverbs, my brother once, to gratify him dou

bly, said, "Mr. Moore, neighbors should RUS.

be neighborly," and set him to measure Y dear lamented brother William his growing family for shoes. He might

Barrington Reade was first a sailor, as well have given the order to Procrustes: then a soldier, then a county squire, and Moore made shoes for shops; he expected had from his youth an eye for character feet to fit his shoes; and, after all, live and live facts worth noting by sea or leather is more yielding than dead. land. He furnished me from his experi- The bill was settled one halfpenny short. ences several tidbits that figure in my From that day, although Moore's converprinted works; for instance, in Hard Cash sations with my brother rambled over vathe character and fate of Maxley, and the rious topics, they always ended one waymanæuvres of the square-rigged vessel at- | “Beg pardon, sir, but there was a halftacked by the schooner; also the mad penny to come last account.” yachtsman, and his imitation of piracy, in Then the humorist would fumble for The Jilt, etc. So now I offer the public this halfpenny, but never find it.

He his little study of a real character in rural used it as a little seton. life.

Moore once related to him his visit to a Indeed, such quiet things may serve to road-side hotel in the old coaching days. relieve the general character of my

work; “I came in mortal hungry, Squire, and for, pen in hand, I am fond of hot pas- there was a table spread. Don't know as sions and pictorial incidents, and, like the ever I saw so much vittles all at one time. historians, care too little for the “middle Found out afterward it was for the pasof humanity."

sengers' dinner. Sets me down just beGeorge Moore, a shoemaker, with a fore the beautifulest bam--a pictureshock head of black hair, a new wife, half takes the knife and fork, and sets there a hundred of leather, and two sovereigns, with my fistes" (pronounced mediævally came over from Ewelme to Ipsden, and ap- fistys”) “on the table, and the knife plied to my father for a cottage on Scott's and fork in 'em. “Landlerd,' says I to Common. It was a very large cottage ; a chap in a parson's tie, 'be you the landthe kitchen between twenty and thirty lerd?' No; he was the waiter. “Then,'

MY

says I, you tell the landlerd I wants to men drank no liquid but beer; the women, speak to 'un very particular'; so presently tea and tadpoles. the landlerd comes as round as a bar'l None of the larger tenants would be mostly. “Landlerd,' says I, with my bothered with “Scott's.” But small farmfistes on the table, and the knife p'inting ers are poor farmers and unsuccessful. uppards, “I must know what the reckon- One or two failed on it, and it was vacant. ing ool be afer I sticks my ferk into't.'” The homestead was a picture to look at,

and in the farm-yard a natural cart shed, Somebody with whom he traded wanted perhaps without its fellow, an old oak-tree one shilling and tenpence more than his twenty-seven feet in girth, and of enordue in a considerable transaction. Mooremous age. The top was gone entirely; so made the parish ring.

was the inside. Nothing stood but a However, he appears in this case to have a large hollow stem with three or four thought he owed mankind in general, and vertical chasms, one so broad that a Scott's Common in particular, an expla- cart could pass into the wooden funnel. nation, so he gave it to the gamekeeper, Yet that shell put out the greenest oak Will Johnstone, Johnstone retailed it at leaves in all the country-side. An artist the “Black Horse," and round it came to could have lived at Scott's Farm and made my humorist, via the gardener.

money. But the acres attached to the de** Ye may say one shilling and tenpence lightful residence made it a bad bargain is a very little sum. Here's Moore run- to farmers; for the acres and the low rent ning all over the parish after one ten. tempted the tenants to farm. But it's a beginning. A text is a little Now you must understand that for a thing; but parson can make half an hour's long time past Ireland has been telling sermon on't.”

England a falsehood, and England swalRustic Oxfordshire has never within lowing it for a self-evident trutlı, and the memory of man accepted that peevish building rotten legislation on it, viz., rule of the grammarians, “Two negatives that the rent is the principal expense of a make an affirmative.” We have a gram- farm. matical creed worth two of that. We It is not one-fifth the expense of a wellhold that less than two negatives might be tilled farm; and of an ill-cultivated farm taken for an affirmative, or at least for an not one-tenth, for it is the last thing paid. assent.

Scott's Farm was one out of a hundred A Cambridge man, whom his college, examples I have seen. The rent of sevenSt. John's, transplanted into my county ty-five acres, plus a charming house and as an incumbent, declared to me once that homestead, was fifty pounds. Yet one he heard a native of my county address bad farmer after another broke on it, and a band of workmen thus: “Ha’n't never grumbled at the rent, though it could not a one of you chaps seen nothing of no have been the rent that hurt him, for he hat?"

never paid it. Moore accumulated negatives as if they Well, Mr. Moore called on my brother, were halfpence. A neighbor to whom he and offered to rent Scott's Farm... had now and then lent a spade, or a fry- My brother stared with amazement, ing-pan, or a fagot, offended him, and they then said, dryly, “Did you ever do me an slanged each other heartily over the pal- injury?" ings. Moore wound up the controversy “Not as I know on, Squire; nor don't thus: “Don't you never come to my house mean to." for nothing no more, for ye won't get it.” “Then why should I do you one ?

The population of Scott's Common is Scott's? Why, they all break on it." sparse, but the dialogue being both long “Oh!" said Moore, “ folk as ha'n't got and loud, seven girls had collected, from no head-piece, nor no money neither, are four to thirteen years old. With this bound to break on a farm. 'Tain't to say assembly Moore shared his triumph. George Moore is a-going to break." " There, you gals, I have sewed up his My brother replied: “Oh, I know you stocking,said George Moore.

are a good judge of live stock, and I dare Scott's Farm was a small holding sur say you have picked up a notion of farmrounded by woods, flat enough when you ing. But you see it requires capital.” got up to it, but on very high ground. “Well, Squire," said the shoemaker, Not a drop of well water for miles. The “I'm not a thousand-pound man, but I'm

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