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was naturally suggested to Forbes by his having previously observed the extraordinary permeability of mica to radiant heat. At the time of his earliest and unsuccessful experiments Sir David Brewster had written him a letter in which he suggested as a mode of polarizing heat, among others, the reflection of heat from mica bundles. This suggestion was not put in practice at the time, and appears to have been entirely forgotten by Forbes when he adopted the use of a similar apparatus for polarization by transmission. These experiments, taken in conjunction with those carried on at the same time by Melloni and others, established the identity of action, under similar conditions, of light and radiant heat, forming a most important step in the investigation of the nature of both, and contributed in no trifling degree to the great advance which this branch of physics has since achieved.

of which is appended to Forbes's volume on Norway, published in 1853. They then went to Switzerland, and, having met Prof. Agassiz by appointment at the Grimsel Hospice on the 8th of August, proceeded by his invitation to spend some time with him on the Unter-Aar glacier.

For three weeks afterwards they were engaged together daily upon the ice, sharing at night the shelter of the same rude hut, under one of the huge blocks of the medial moraine of the glacier. The general fact of the downward movement of glaciers had long been known, although it is related that a certain professor of Tübingen, after a brief visit to those of Switzerland, went home and wrote a book fatly denying the possibility of their motion. The first attempt to form a glacier theory was that of Scheuchzer in 1705. He supposed the motion to result from the conversion of Another important investigation con- water into ice within the glacier, the expanducted by Forbes with respect to the prop- sion so caused furnishing the force which erties of heat related to thermal conduc- impelled it downwards. This theory, tivity. He was the first to point out and adopted and illustrated by M. de Charpenthis at a very early period of his career tier, has since been associated with his name. the fact that the conducting powers of the De Saussure, following Altmann and Grümetals for electricity are approximately ner, concluded that the glacier reposing on proportional to their conducting powers for an inclined bed, slid down by little and litheat. Now, heat diminishes materially the tle, as a solid mass, towards the valleys. electric conducting power- does it also M. Rendu, Bishop of Annécy, who died in affect the thermal conductivity? Forbes | the autumn of 1859, published in the Meshowed that, at least in the case of iron, moirs of the Royal Academy of Sciences of the only metal his failing health left him strength to examine, the conductivity for heat diminishes as the temperature increases. Another result of the same investigations, and one of great interest and importance in modern science, is his determination (the earliest of any real value) of the absolute conductivity of a substance, i. e. how much heat passes per second per unit of surface through an iron plate of given thickness, whose faces are maintained at constant given temperatures. As a proof of the value attached by scientific men to these ingenious experiments, it is only necessary to mention that the British Association has given a grant for their repetition with the best attainable instrumental means, and for their extension to other substances than those to which Forbes was compelled to confine himself.

In the months of June and part of July, 1841, Forbes was engaged in exploring the volcanic countries of Central France, an account of the results of which expedition is contained in a paper in the twentieth volume of the Edinburgh Phil. Transactions. The remainder of July was devoted, in company with Mr. Heath of Cambridge, to excursions in Dauphiné, an account of part

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Savoy, in 1841, an essay entitled Théorie
des Glaciers de la Savoie, in which he for
the first time directed attention to the
different rates of motion of different parts
of the same glacier, and especially to the
fact that the centre of the glacier
more rapidly, while the sides are retained
by the friction against its rocky walls."
M. Rendu also remarks that "between the
Mer de Glace and a river there is a resem-
blance so complete that it is impossible to
find in the latter a circumstance which does
not exist in the former - the friction of the
bottom, that of the sides, the action of ob-
stacles, cause the motion to vary, and only
in the middle of the surface is this entire."
The first person who made quantitative
observations of the motion was Hugi, who
found that from 1827 to 1830 a cabin
erected by him on the Aar glacier had
moved 100 métres, or about 110 yards,
downwards; and in 1841 M. Agassiz found
it at a distance of 1428 mètres from its
original position. We have thought it
necessary to give these details regarding
the state of the question at the time it was
taken up by Forbes, as the importance of
the contributions which he made to the
knowledge of the subject has perhaps been

exaggerated on the one hand, while it has been as much depreciated on the other. The general analogy between the motion of a glacier and that of a river had been clearly pointed out by Rendu, but the obvious difference between the solid ice and the mobile elements of a stream remained, and how this solid mass could present phenomena similar to those of a liquid remained to be accounted for. By his observations on the Aar glacier, and subsequently by those on the Mer de Glace, Forbes examined these phenomena in detail, and in four letters to Prof. Jameson (1842, Ed. Phil. Journal, 1842-3), and more fully in his Travels through the Alps of Savoy and other parts of the Pennine Chain (Edinb. 8vo. 1843), propounded his theory known as Viscous or Plastic Theory." This theory is shortly expressed by himself in these words: "A glacier is an imperfect fluid or viscous body, which is urged down slopes of a certain inclination by the mutual pressure of its parts."

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his interesting narrative of alpine scenes and adventures contributed not a little to kindle the enthusiasm with which such scenes have since come to be regarded by succeeding mountaineers.

The Travels through the Alps was followed by his Norway and its Glaciers (Edinb. 8vo. 1852), the narrative of a journey undertaken in the summer of 1851, to which was appended Journals of Excursions in the High Alps of Dauphiné, Berne, and Savoy (made in 1839 and 1841), and by The Tour of Mount Blanc and Monta Rosa (ib. 1835), an abridgement of the larger work. In 1849 Forbes published The Danger of Superficial Knowledge, an introductory lecture delivered Nov. 1848, and in 1854 he contributed an essay on The Geology of the Cuchullin Hills to The Guide to the Island of Skye. In 1859 he published Occasional Papers on the Theory of Glaciers (Edinb. 8vo.), a collection of his minor papers on the subject, with a " prefatory note on the recent progress and present aspect of the " "Theory of Glaciers." These include the paper on glaciers contributed by Forbes to the 8th edition of the Encyclopædia Britannica, for which he also wrote Dissertations on the Progress of Mathematical and Physical Science, already referred to. His last publication, 1860, was a Reply to Prof. Tyndall's remarks in his work on the Glaciers of the Alps relating to Rendu's “ Théorie des Glaciers." (Edinb. 12mo.) He was moreover a not unfrequent writer in the Edinburgh and Quarterly Reviews. We may especially mention an interesting article contributed by him to the latter (No. 202, April 1857,) entitled "Pedestrianism in Switzerland."

This theory was further explained and illustrated in subsequent papers which appeared in the same journal between 1844 and 1850, and it certainly conveyed a more clear and lucid general conception of the phenomena than had ever been previously advanced. Prof. Tyndall has since sufficiently exposed its weak points. It must be conceded that the term "viscous" was not happily chosen. Ice under pressure has a decided plasticity, but it is so far from being viscous that a very small strain is sufficient to interrupt its continuity.* Forbes, who was always most modest in the assertion of his own claims as a scientific discoverer, was deeply hurt by the insinuation which appeared to be conveyed by Prof. It is to be feared that his alpine labours Tyndall's observations, that he had not and the exposure which they necessitated sufficiently acknowledged the prior state- resulted in the serious injury of his health. ments and theories of Rendu. Hence arose His Theory of Glaciers is dedicated to his a controversy which became almost person- friend Dr. Symonds, of Clinton Hill House. al, and therefore painful to the friends of Bristol, under whose care he had been comboth parties, but which was not unservicea-pelled to place himself. In 1860 he was ble in the further elucidation of the subject. But, besides the theoretical portion of his work, Forbes accumulated a large amount of accurate observations, illustrated by maps and views of glaciers, the first which had appeared with any approach to truthfulness. He was also the first to call attention to numerous important glacial phenomena, such as the dirt bands," "veined or ribboned structure," &c. while

We believe, however, that the change of form undergone by a glacier in its motion is mainly due, as stated by Forbes, to plasticity under pressure, and only to a minor extent to the "fracture and regelation" to which it is ascribed by Professor Tyndall.

obliged to resign his professorship, having continued to perform its duties for several years in spite of bodily weakness. In the same year he was appointed Principal of St. Andrew's, in which office, though its labours were less severe, he was able to render most valuable service.

The Pall Mall Gazette justly remarks on this portion of his career,

All who came under Principal Forbes's intellectual and moral influence looked up to him with reverence, and even with enthusiastic admiration, while among his friends he was regarded with a singular degree of affection. In ordinary intercourse nothing could be more

simple and gentle than his demeanour; it was at the same time that courteous and deferential manner which characterized the high-bred gentleman of a period that has all but passed away, and of which, if we have parted with the formality, we have also lost much of the refinement; and under that manner there was the utmost sincerity, guilelessness, benevolence, and sympathy. It has happened to few to be at once so reverenced as a philosopher and so beloved as a friend. He was cherished by great men who have gone before him, Arago, Whewell, and Brewster, and he will be deplored by many great men who yet remain, Herschel, Airy, Sedgwick, Murchison, and Thompson, who well knew his services to science and who were attached to him as a friend and fellow-labourer.

Between 1828 and 1862 he published no less than 118 important memoirs on scientific subjects. Of these 101 appeared before 1852. He received the Keith medal of the Royal Society of Edinburgh on three occasions, and the Rumford and other medals of the Royal Society of London for various papers contributed by him to the Transactions of these bodies. He also received the honorary degree of D.C.L. from the University

of Oxford in June 1853, was a fellow of the Royal and Geological Societies of London, and for many years secretary of the Royal Society of Edinburgh. The Alpine Club on its first establishment in 1858 had elected him an honorary member, and the Institute of France had conferred upon him its corresponding members. A similar honin 1842 the high distinction of being one of our had been voted him by the academies and scientific societies of Palermo, Haarlem, Rome, Berne, Heidelberg, Geneva, and Vaud, and he was an honorary member of the Royal Medical Society of Edinburgh and numerous other institutions. In the after part of last year he was compelled to relinquish the Principalship of St. Andrew's, and again to place himself under the care of his friend Dr. Symonds at Clifton, where he died, as we have already stated, on the last day of the year. He inarried, in 1843, Alicia, daughter of Mr. George Wauchope of Edinburgh, by whom he had a family of two sons and three daughters, and who survives him.

R.C.N.

A RECENT number of an Italian journal in this mies of progress attempted by every means in city pays a just tribute to the eminent services their power to give the semblance of truth. Nor of our countryman, Mr. Henry T. Tuckerman, were the writings of Tuckerman confined to the in behalf of the literary and political interests American Union. The reformed ministry, being of Italy, for which he has just been honored by anxious to know the impression which their bold the King with the Insignia of the "Order of projects had produced abroad, instructed the Officer of the Crown of Italy." In the article representatives of their Government to collect to which we have referred, the writer says: " Mr. and forward whatever came to light on this subTuckerman, who in early youth resided for some ject in the countries to which they were accredtime in Italy, has not only studied the liberal as-ited. In consequence of this request, the works pirations of the country, the obstacles by which of Mr. Tuckerman were sent to Italy, and their she has been cramped for ages, and the hidden salutary effect was soon recognized by Cavour, treasures of her resources and power, but has who expressed his gratitude in a letter to the treated the problem of her resurrection, in vari- author, full of the most flattering acknowledg ous literary works of great elegance and bril- ments, which he wrote in the midst of the liancy, showing to his countrymen how much gravest cares of State. We have already said sympathy was due to those who had attempted enough to call forth the grateful feelings of every to free themselves from the ancient slavery to Italian towards this writer. But the interest which they had been condemned by incessant for- which he has always taken and always will take eign invasions and protracted despotism. It is in the affairs of Italy is not restricted to his. owing in a great measure to the Italian Sketch writings. His activity and zeal were conspicuBook,' Sicily,' Biographical Essays' on Pe- ous in collecting the contributions which were so trarch, Alfieri, Ugo Foscolo, Pellico, Leopardi, generously offered by the Americans in the wars D'Azeglio, Garibaldi, and various other essays of 1848 and 1859. How warm and sincere a and articles which treat the subject with exquisite taste and profound knowledge, that the national programme which was conducted with so much energy and wisdom by the supreme genius of Cavour, found in the United States so many generous friends and advocates, and that public opinion was not led astray by the false reports to which the clerical reaction party and the ene

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friend to Italy and the Italians Mr. Tuckerman has proved himself is well known to all the distinguished exiles who within the last twenty years have sought repose under the free institutions of that noble republic, and found in him a cheering support in their exile."

N. Y. Tribune.

CHAPTER XIX.

READ BY ANOTHER'S EYES.

ON looking at the picture, the next day, Bella was painfully dissatisfied with her work. What she had done with so much care and diligence seemed to her false in drawing and expression. She grew positively angry over it, and would have made a fresh beginning had not Clodwig, by his gentle persuasions and judicious praise of the many excellencies of her picture, succeeded in soothing her. She could not help saying, however, with some bitterness, that it was her fate to have everything she undertook turn out otherwise than she had desired, and upon Clodwig's assuring her that such was the necessary result of every attempt to embody our conceptions, she exclaimed impatiently, "I am not what I am." The real cause of her discontent was hard to determine. It was more than the mere dissatisfaction of the artist and disappointment in her own powers.

The strict discipline which Eric had wished to maintain was now much broken in upon. Bella always carried through whatever plan she had laid out for herself, acting upon her favorite theory that it was well to allow men to think they had some authority, but that must be all.

life's journey, "Follow thou me." We moderns must recognize what is pure and lofty in noble natures, though cramped by the many limitations incident to our age and individual constitution.

Bella's pencil worked rapidly while he was speaking, and she often nodded her head assentingly. When he ended she

looked full at him, and said, —

You are the best teacher I ever met with;" then, with beaming eyes and glowing cheeks, she turned again to her work.

"That depends upon the pupil," answered Eric, politely acknowledging the compliment.

"I want you, now," continued Bella, still blushing deeply, "I want you to lay your hand on Roland's head. Please do; it will give precisely the effect I desire. Please do as I say.'

He consented, protesting at the same time that the idea did not please him, for Roland should learn to carry his head free.

Bella shook her head with vexation, and continued her work, no longer, however, on the figure of Eric, but solely on that of Roland.

"Now I have it!" she suddenly exclaimed; "that is it! You resemble Murillo's St. Anthony."

66

That is just what I noticed," cried Roland. "Manna scolded me for it at the musical festival."

Clodwig also agreed with his wife.

Roland soon turned the conversation to the subject always uppermost in his mind, the life of Franklin. Bella expressed a wish to learn something about it, and Clod- "It is a favorite picture of mine," he wig, after a little sketch had been given of said. "How plainly I can see it now bewhat had been already gone over, was fore me! The figure of Anthony on his quite ready to resume the reading where it knees, with a knotted staff beside him; the had been dropped before. Eric and Ro- landscape barely indicated; a tree in the land, who sat upon a raised platform, list-background, and the thicket near by. Anened eagerly. The reading gave rise to many an animated discussion, for Bella entered with remarkable ease and readiness into everything that was presented to her. Eric was disturbed by her speedy detection in Franklin of "a certain dry pedantry, a stinginess of nature," which her acute criticisms set forth in strong relief. He could feel the emotion her words caused in Roland, who was sitting on his knee.

In these days, it is impossible for a young man of Roland's antecedents and present position to preserve a perfect ideal. If rightly guided, and established on a solid footing, it might perhaps be useful for him to see his ideal attacked, and even distorted.

gels are playing on the ground and floating in the air; one turns over the leaves of the Saint's book, while another holds up to an angel hovering in the heavens a lily which has grown from the earth; the flower thus forming, as it were, a link between heaven and earth."

Eric was somewhat embarrassed by Roland's relating how he had fallen asleep in the chapel of the convent, and how suddenly the black nun stood beside him, and he saw the picture above him.

A request of Eric's that the reading might stop here, and the reasons on which he based his request, assumed various shapes in the minds of his hearers.

66

To-day's experience convinces me."
that we
cannot control our

With all the eloquence at his command, he said, Eric stated the difficulty that beset the en- thoughts or pursue them to any worthy lightened mind of the present day, in hav- issue, when obliged to remain in a position ing no authoritative voice in the place of foreign to those thoughts, or in one at least that of the Church, to say at every point of that has no connection with them. There

is a mysterious sympathy between our thoughts and the position and state of our bodies."

Eric's words worked in four different

convent, and add this to the many other experiences of his past life which Manna would have to forget.

Lina meanwhile received his attentions

There was a constant stream of jesting and laughter in the Villa and park. One day Pranken induced his brother-in-law to go boating with Lina and himself, while Bella remained at home to draw. He wanted to take Roland also, wishing, with a certain recklessness, to leave the other two alone together for once. But Roland would not leave Eric; he even openly avoided Pranken's society.

ways upon the party assembled. In his very unconcernedly, showing equal friendliown case, they served to describe his posi-ness of manner towards both him and Eric, tion as tutor. Roland thought of the ma- whom she always called her brother in sons at work on the castle, and wondered music. what they must be thinking of while perched in mid air on their scaffoldings, or while hammering the stone. Clodwig, too, must have found the words bear in some way upon his life, for he shook his head and pressed his lips hard together, as he was wont to do when thinking. But upon Bella they produced the most striking impression; she suddenly let fall from one hand her pencils, and from the other the bread which she used for the occasional erasing of a line. Eric instantly restored them to her, and she took them from him with a vacant look and no word of thanks. He had brought before her the picture of her married life. Thus this one key-note had struck four different chords.

For a long time no word was spoken. The presence of Clodwig and his family at Villa Eden caused great excitement in the neighborhood, and appeared to place the tutor in a very peculiar position. Pranken, however, viewed the matter quite differently, and, as acknowledged son of the house, invited to Villa Eden the Justice, with his wife and daughter, who had just returned from the Baths.

His manner towards Lina was particularly friendly and intimate; he took long walks in the garden with her, and made her tell him about her life in a convent, which she did most amusingly, giving comical descriptions of the sisters, the Superior, and her different companions. Her only object in staying at the convent had been the learning of foreign languages. Lina's perpetually gay spirits began to have a cheering effect upon the melancholy Pranken. Something of the Pranken of old times was roused within him. Why need the present be empty and barren? it said. Bella has her flirtation with the Captain, why should he not have his with Lina? Why not. indulge in a little harmless jesting, perhaps even admit the excitement of some feeling? He could control himself at any moment.

The old Pranken, the Pranken of the days before, seized his rescued moustache with both hands and twirled it in the air.

It was a good idea, during this pause in his life, to amuse himself with the Justice's Lina. He could imagine himself transported back to the days before that visit to the

Lina sang gaily as they sat together in the boat. Her love-songs were given with a sweetness, an abandonment, that Pranken had never heard from her before. Clodwig described her singing to his wife, on his return, as being as simple and beautiful as a field flower.

Bella begged the Justice and his wife to let her take Lina back with her to Wolfsgarten. The Justice's objections were overruled by his wife, and Lina was full of delight at setting off with Bella and Clodwig. Pranken rode beside the carriage.

The quiet of this loneliness weighed heavily again upon Eric and Roland, after the animated society of the last few days. Eric, beside, was out of tune, weary and dull. He found it a burden to be obliged to devote himself from morning to night to this boy, to have to watch his undisciplined, and often capricious, fluctuations of mind. He longed for the society of Clodwig; still more, though he hardly acknowledged it to himself, for that of Bella. There had been a novelty, an animation, an excitement, an atmosphere of graceful elegance, about the rooms, which were now so desolate. Nevertheless, he resisted for several days Roland's entreaties that they should make the promised visit to Wolfsgarten. The house had been entrusted to his care, and he refused to leave it, until Pranken, at length, offered to take all the responsibility upon himself. There was a sting in his words, as he said to Eric,

"You were present at the musical festival, and left the house then in charge of only the servants. Besides, as I say, I assume the entire responsibility."

CHAPTER XX.

ENTERING INTO THE LIVES OF OTHERS.

BEAUTIFUL it is in the valley, on the river's

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