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was proved to demonstration. The intermittent, made by bringing a screen Astronomer Royal took a strong view before the flame; and there are double of the case, saying of one instance: “It lights—for instance, the double revolving “ really gave me a feeling of melancholy light at the Calf of Man, the ludicrously “ to see the results of such exquisite characteristic effect of which I well “ workmanship entirely annihilated by remember, as it seemed to wink at our “subsequent faults in the mounting and passing boat, first with one and then " adjustment." The attention of the with the other of its fiery eyes. On Trinity Brethren was called to this the night after that fearful day when defect; and, by the zealous co-operation the Royal Charter was wrecked, I stood of Professor Faraday and Mr. James on the pier at Honfleur ; and, while the Chance, means were devised for re- vessels were tossing about, the desirableadjusting the bands of glass, or for fixing ness of good distinctions was deeply them properly in the first instance. impressed on my mind for there, at the During this investigation several mouth of the Seine, were eleven dif. curious facts were noticed. Thus sailors ferent lights, most of them having just at Whitby had complained that the the same appearance; but among them lighthouse gallery cut off the lower stood conspicuous and unmistakeable the beams of light; it was not the gallery, light of Fatouville, alternately steady but the very prisms of glass which ought white, dull red, red flash, dull red, to have gathered up that light for the steady white. There is something benefit of the sailor. The revolving light peculiarly impressive in the constant at Cape Gris Nez has been praised both change of white, white, red, at regular in parliament and out of it, and has intervals, in such a lonely situation as drawn upon itself the special admira- the Tuskar or Cape Wrath, when seen tion, not only of those landsmen who on a dark night from the deck of a ship may run across by night from Folke- sailing on to the wide Atlantic. stone to Boulogne, but also of the New sources of light. Why should seamen who frequent the whole of the we be confined to the combustion of British and French waters. Yet the oil ? The Pharos of the future will French authorities thought rather perhaps be as independent of it as is meanly of the light at Gris Nez:-it our present street lamp. was an old-fashioned thing, one of the Coal gas. Though the use of gas has first dioptrics put up, without any of been frequently pressed upon the attenthe modern improvements. The com- tion of the great lighthouse authorities, mission visited Gris Nez; and, true they have never adopted it, conceiving enough the apparatus was old fashioned it to be dangerous. The municipal But it was accurately adjusted-probably bodies, however, have not participated by Fresnel himself; at any rate by some in this dread, and a large proportion of one who was not content with ordering even the most important harbour lights a beautiful, complicated, and costly piece owe their illumination to this source. of mechanism, and getting a mason to Some of these are admirably managed set it on top of a tower.
and most efficient; but there are others It is not in the above respects alone which present a sad contrast-as that at that great ingenuity has been displayed Dover, of which it is reported : “The in lighthouse apparatus. In order to “green light was only distinguishable distinguish one light from another, some “as the dullest of lights round the are made to revolve, while others remain “harbour, and by a greenish or blueish stationary. The rates of revolution also “hue, not very discernible." vary. Again, while the majority are The same optical apparatus is appliwhite, many are red, and a few green, and cable to a gas as to an oil-flame. some revolving lights are alternately Electric light. All other lights that white and red. There are also other science has produced appear dim beside varieties. There is a bad variety called the the splendour of that small spark which bursts into view when the conducting - was continued for some months, and wires of a powerful electric current are was considered successful. But the separated by a minute space, especially light was afterwards removed from if these wires terminate in charcoal the South Foreland, the dioptric appoints. The worst is, that it is difficult paratus of which was ill-adapted for to maintain this spark in a constant it. Some improvements have since been state of brilliancy. Many attempts made ; and it is now fitted up with have been made to overcome this diffi- optical apparatus of its own, at Dunculty, and many proposals have been geness, and will, probably, be shining submitted for introducing electric lights again before this paper is printed. It into lighthouses; but the only one is intended that it shall be permanent. which has been so introduced is that Professor Faraday, who first discovered of Professor Holmes. In 1853 he was magneto-electricity, and who is the called to examine some magneto-electric scientific adviser of the Trinity House, machines that were intended for the has naturally taken a great interest in decomposition of water, and it occurred the development of this child of his, to him that they might be made available and in seeing it take a part in the for producing the charcoal light. He active business of the world. got the light, and set to work to perfect Lime light. Captain Drummond atthe apparatus. In February, 1857, he tempted to introduce into lighthouses first communicated with the Trinity the brilliant light produced by the House ; and, on December 8, 1858, incandescence of a piece of lime in an this brilliant star first beamed forth oxy-hydrogen flame; but, at that time, over the seas from a lighthouse—that the difficulty from the cracking of the at the South Foreland—surprising the lime could not be sufficiently overcome. sailors, and the inhabitants on the Mechanical genius, however, has done opposite coast of France. The light, much to remove this, and for three as in other cases, is derived from com- months during the past autumn a light : bustion; but it is the combustion of of this character was exhibited, as an coal in a small steam engine, which experiment, at the South Foreland. rotates a wheel loaded with soft iron S hould either this light or that from cores past another wheel loaded with the magneto-electric machine eventually permanent magnets. This calls into come into general use, England will action a force which, carried aloft by have the honour of initiating an imstout wires and allowed to pass between provement in lighthouse illumination the charcoal points of an ingeniously- equal, if not superior, to that effected in constructed “lamp," produces a light France by the genius of Fresnel. Long which can only be compared to a may there be such a rivalry between the fragment of the sun. The experiment two nations !
THE CURSE OF ROME.
BY RICHARD GARNETT.
[Written after reading Count Montalembert's letter to Cavour, in which
he contends that the temporal power of the Pope should be maintained for the benefit of “the Catholic world.”]
In France throned Despotism's foe and fear,
To quell the aspiring spirit else unbent,
As a Brazilian traveller lulled and bled
Of pictures ; Venice shipless ; where erst flew
And grow! But, as an arid water-course
Romeward ascending. Who art thou would'st go
What! Rome must wither 'neath the oppressor's hand,
Of Paradise ? Can earthly changes mock
Europe's exemplar Helot to deter
Go to that master-labour of the priest
Squalid, and meagre serf—then go, his worst
And hear thou mine, old Church !-- not for the crime
Safety who sails unseen, pleads and atones
Nor only that thou resolutely art
Young Science, lauding whiles with hollowest prate The Might thou wouldst so fain bind and emasculate ;
Not only for the venom thou dost cast
Country, bride, mother-moulded to disdain
Not only for the rack and screw, that wreaked
Nor even the myriad minds thou did'st debase,
Teaching to mock the tortures of the just,
But chiefly that, as birds of carrion find
Trampling with dismal crash and frantic spasm
By Eloquence, Freedon's beloved child,
Of mental night won from the day-spring's burst
Even now the dread Colossus totters, sways,
Soon with new beams illume the eternal dome,
ON THE AGE OF THE SUN'S HEAT.
BY PROFESSOR W. THOMSON, GLASGOW. The second great law of Thermody- be a state of universal rest and death, if namics involves a certain principle of the universe were finite and left to obey irreversible action in nature. It is thus existing laws. But it is impossible to shown that, although mechanical energy conceive a limit to the extent of matter is indestructible, there is a universal ten- in the universe ; and therefore science dency to its dissipation, which produces points rather to an endless progress, gradual augmentation and diffusion of through an endless space, of action inheat, cessation of motion, and exhaustion volving the transformation of potential of potential energy through the material energy into palpable motion and thence universe. The result would inevitably into heat, than to a single finite me
chanism, running down like a clock, i See Proceedings R.S. E. Feb. 1852, or Phil.
and stopping for ever. It is also imMag. 1853, first half year, “On a Úniversal Tendency in Nature to the Dissipation of
possible to conceive either the beginning
possible to conceiv Mechanical Energy."
or the continuance of life, without an