of all rival churches in a common Christianity by the downfall of the spiritual supremacy of the Roman See. But though the distinction of Catholic and Protestant is never likely to cease, we do trust a day is approaching when the withdrawal on either side of exploded sophistries and obsolete claims will breed a more generous rivalry and a closer sympathy of action, if not of faith; when there will be as little disposition on one side to clothe the expressions of honest conviction in the distorted imagery of apocalyptic wrath, as on the other to reunite the chain of the 'past,' as was proposed the other day by the Archbishop of Toulouse, by a solemn commemoration of former religious massacres. For one hundred years past,' says Dr. Döllinger, 'the whole course of development in Europe has led to thisand we may see in it the hand of Divine Providence-that 'Protestants and Catholics have been approaching each other 'more and more.' Nothing is likelier to contribute to such a result than the cessation of the Temporal Power. It will remove from the Roman Catholic Church many causes of heart-burning and jealousy, and of scandal to those without her pale, without weakening by one iota her spiritual influence indeed, it will probably increase it.

6

The importance of the present crisis to the religious interests of Europe it would not be easy to exaggerate. Let it be borne in mind that, while during the last few years vigorous attempts at proselytism have been made, with more zeal than discretion, no inclination towards Protestantism has manifested, or seems likely to manifest itself in Italy. On this point Protestant and Catholic testimony is agreed. All that has occurred there has but given additional force to Lord Macaulay's observation made many years ago, that, since the period of the Reformation, no 'Catholic country had lost its Catholicism without losing its 'Christianity too.' Let this be borne in mind, and then let it also be remembered, that for every month and every week the Pope remains at Rome, guarded by foreign bayonets against the legitimate political aspirations of an indignant people, reverence for his person and office, and, what is still more serious, for the faith of which he is the representative, is losing its hold on the Italian nation, and, in a lesser degree, on the Catholic populations of Europe.

No. CCXXXVI. will be published in October.

THE

EDINBURGH REVIEW,

OCTOBER, 1862.

No. CCXXXVI.

ART. I.-1. Researches on the Solar Spectrum, and the Spectra of the Chemical Elements. By G. KIRCHHOFF, Professor of Physics in the University of Heidelberg. Translated by HENRY E. ROSCOE, B.A., Professor of Chemistry in Owens College, Manchester. Cambridge and London: 1862. 2. Chemical Analysis by Spectrum Observations. By Professors BUNSEN and KIRCHHOFF. Memoirs I. & II. POGGENDORFF'S Annalen (Philosophical Magazine, 4th Series, vol. xx. p. 89., vol. xxii. p. 1.). London, Dublin, and Edinburgh. IT is unnecessary to insist, at the present day, upon the incalculable value of discoveries in natural science, however abstruse they may be, or however far-distant may appear their practical application. If we put aside for the moment that highest of all intellectual gratifications afforded by the prosecution of truth in every form, the perception of which is one of the chief distinctions of human from mere brute life, and if we look to the results of scientific discovery in benefiting mankind, we find so'many striking examples of the existence of truths apparently altogether foreign to our every-day wants, which suddenly become points of great interest to the material prosperity and the moral advancement of the race, that we are less apt to utter the vulgar cry of 'cui bono' respecting any scientific discovery; and if we are not advanced enough to love science for the sake of her truth alone, we at least respect her for the sake of the power she bestows. Not once, but oftentimes in the annals of science, it has turned out that discoveries of the most recondite truths have ere long found their application in the physical structure of the world, and even in the common interests of men; for in the range of scientific inves

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tigation, it can never be said how near the deepest principle lies to the simplest facts.

A great discovery in natural knowledge, for which no equivalent in direct benefit to mankind has as yet been found, but which nevertheless excites our liveliest interest and admiration, has lately been made in the rapidly advancing science of Chemistry. This discovery, which is one of the grandest and most important of all the recent additions to science, consists in the establishment of a new system of chemical analysis-of a new power to investigate the constitution of matter. This is of so delicate a nature, that, when applied to the examination of the substances composing our globe, it yields most new, ,interesting, and unlooked-for information. At the same time it is of so vast an application as to enable us to ascertain with certainty the presence in the solar atmosphere- at a distance of 95,000,000 miles of metals, such as iron and magnesium, well known on this earth, and likewise to give us good hopes of obtaining similar knowledge concerning the composition of the fixed stars. Here, indeed, is a triumph of science! The weak mortal, confined within a narrow zone on the surface of our insignificant planet, stretches out his intellectual powers through unlimited space, and estimates the chemical composition of matter contained in the sun and fixed stars with as much ease and certainty as he would do if he could handle it, and prove its reactions in the test-tube.

How can this result, at first sight as marvellous and impossible as the discovery of the elixir vitæ or the philosophers' stone, be arrived at? How did two German philosophers, quietly working in their laboratory in Heidelberg, obtain this inconceiv able insight into the processes of creation? Are the conclusions which they have arrived at logical consequences of bonâ fide observations and experiments- the only true basis of reasoning in physical science or do they not savour somewhat of that mysticism for which our German friends are famous? Such questions as these will occur to all who hear of this discovery; and it will be our present aim, in reviewing the publications which are placed at the head of this article, to answer these and similar questions, and to show that, far from being mystical, these results are as clear as noon-day, being the plain and necessary deductions from exact and laborious experiment. And here we may express our satisfaction at the change which has occurred within the last few years in the direction given to the powerful intelligence and the indefatigable industry of Germany. The labours of the Germans in physical science have far surpassed in their results those speculative researches

which had rendered German philosophy' the synonym of all that was unintelligible and perplexing: and it is impossible to overrate the services which men like Liebig and Bunsen (the chemist) and Kirchhoff have rendered to mankind. In chemistry, Germany may now be said to take the lead of England, of France, and of Italy: already she has paid an ample contribution to the common stores of human knowledge. It is a remarkable circumstance that although for several years the once productive fields of German literature have been comparatively barren, or have at least presented us with no work of the highest order, the supply of German works on natural science is immense, and the quality of these works excellent.

The only channel through which we on the earth can obtain information of any kind whatever concerning the sun and stars, consists in the vivifying radiance which these luminaries pour forth into surrounding space. The light and heat which we receive from the sun not only supply the several varieties of force which we find in action upon the surface of the earth, thus rendering the whole human family truly children of the sun; but a knowledge of their nature enables us to ascertain the chemical composition of those far-distant bodies upon which the existence of our race so intimately depends. The examination of the nature of sunlight and starlight has led to the foundation of a science of stellar chemistry; and it is likewise upon the examination of the light given off by terrestrial matter, when through heat it becomes luminous, that the new method of spectrum analysis is founded—a method so delicate as to enable the analyst to detect with ease and certainty so minute a quantity as the 1800 part of a grain of substance.

The world owes to the great Newton its first knowledge of the nature of sunlight. In 1675 Newton presented to the Royal Society his ever-memorable treatise on Optics; and amongst the numerous important discoveries there disclosed and recorded, was one demonstrating the constitution of white light. He describes what he observed when he passed a beam of sunlight, from a hole in the shutter of a darkened room, through a triangular piece of glass called a prism. He noticed that, instead of a spot of white light corresponding to the hole in the shutter, a bright band of variously coloured lights, showing all the tints. of the rainbow, was thrown on the wall of his room. Newton concluded that these colours were no peculiar effect of the prism, because a second prism did not produce a fresh alteration of the light. He showed that the white light is thus split up into its various constituent parts; and by bringing all these