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The water is derived from three sources: from the melting of the ice or snow next the earth, from the natural heat of the earth; from the melting of the surface of the ice and snow from six to eight feet deep, semi-annually, by the heat of the sun and warm atmosphere; and from the fall of rain in thunder-showers and other rains. Consider its quantity. The upper source of a glacier, the névé, covers many square miles. The light flaky snow is soon changed by the water and cold into a granular crystalline form, and ultimately, as this descends, from pressure, into ice. The amount of water can best be approximated by the River Rhone, which issues from the Aar glacier, or by the Arveiron, which runs from the bottom of the Glacier des Bois. The last was measured at its source by Prof. Forbes in September, when the flow was much less than in the two preceding months. Forbes estimated the water to be three hundred (300) cubic feet a second. This would give in an hour 1,080,000 cubic feet, equal to 67,500,000 pounds of water for hydrostatic pressure. In July the amount is double at least, and in February not half as much probably. Still the Arverion runs through the winter. A canal twelve feet long, five feet deep and five feet broad, would hold three hundred cubic feet, the discharge of Arveiron in one second; in one minute, sixty times as long; and in one hour sixty times longer, or more than eight miles. The Arveiron was visited by Tyndall, Dec. 29th, 1858, after a very cold period. He says: "The quantity of water issuing from the vault was considerable. It was turbid with suspended matter, though not so turbid as in summer. This character of the water could only be due to the grinding motion of the glacier upon its bed a motion not suspended even in the depth of winter. The temperature of the water was the tenth of a degree Centigrade above zero" (just below

The area of the mountain basin to which the Mer De Glace bel from whose snows it is supplied, is estimated to be thirty square miles of this is said to be naked rock, which must be covered with snow and the waters of which must pass downwards to increase the Arve glacier proper covers more than five square miles. The Arveiron two miles above the village of Chamouni. (Johnson's Physical Vol. xxviii.-21.

32 deg. Fah.); "that of the ice was half a degree below zero" (not a degree below 32 deg. Fah.); "this was also the temperature of the air." This occurred when the mean of the minimum temperature for fourteen days had been 15.3 deg. Fah.

Let us then suppose that next winter all the water shall be discharged, and the Arveiron cease to flow by the middle of February; that the glacier becomes a mass of solid ice, and the cold great enough and long enough to freeze the glacier to the earth; that this condition extends from the lower end of the glacier to the highest névé that now sustains and feeds it; will the glacier move at all along the inclined surface? All declare, "No." Suppose, next, that the natural heat of the earth just destroys the frost that binds the glacier to the earth, so that the glacier merely lies on its bed as gravitation requires. Not a particle of water has fallen upon it; not a mite of snow has melted on or under its surface; it lies in the valley of greater or less inclination, just as it was frozen fast; will the glacier now move onwards, or will it preserve its position? In what respect does it differ from an equal mass of rock lying just as loosely upon the earth, especially in the cause of any motion? The rock would not move, would be the universal opinion. To our mind it is clear, that the glacier would not move.

But what is the difference between the glacier now and when it was moving down the incline last June? Simply, that it is not permeated with water, and that water is not passing, as then, from the névé through the whole length of the glacier, from the surface to the bed. Every element of force is precisely the same as then, unless modified by the water. But if water is the modifier, then the plasticity depends upon it. Then we have learned how gravitation operates on the snow and ice, by means of the water of the glacier, in moving, and moulding, and fitting it to the sinuosities, and obstacles, and changes of inclination, which occur in its descent. Prof. Forbes says: " of the influence of temperature on the motion of the Mer de Glace," in the spring evidently, that the glacier "took no real start until the frost had given way, and the tumultuous course of the Arveiron showed

that its veins were again filled with the circulating medium to which the glacier, like the organic frame, owes its moving energy." (Tyndall, p. 338.) A quotation of similar character from Forbes has already been given. If Prof. Forbes is authority, the infiltrating water is essential to the motion of a glacier.

This "influence of temperature" mentioned by Prof. Forbes, has respect only to the melting of the ice to yield the water necessary for the motion; that is, when the Arveiron began to be "tumultuous" in its flow, the motion of the glacier was increased. The temperature of the glacier is proved by Agassiz and Tyndall to be the same in general for summer and winter, or near 32 deg. Fah., at which temperature both ice and water exist together. We shall of course notice the figurative language of Forbes, and shall not believe that a glacier has veins like an animal, or even capillaries, or that the circulation in a glacier has much analogy to that of high organic life. The glacier is not an organic body; it has no organized structure; it does not act according to any laws of life. Its operations are according to the physical laws of inert

matter.

We have presented so full a view of Tyndall's " Glaciers of the Alps," because we are so far removed from such objects and phenomena, because much of error has been published on the subject, because of the intrinsic interest of the object, and because of the fulness of the details which enable us to have an adequate conception and enjoyment of the subject,

ARTICLE VI.-RECENT PUBLICATIONS.

THEOLOGY AND RELIGION.

The Life of our Lord upon the Earth, considered in its Historical, Chronological and Geographical Relations. By SAMUEL J. ANDREWS. New York. Charles Scribner. 1862. pp. 450.

The purpose of the author of this work is not to discuss the inspiration, the authorship, the date, or the relative characters of the Gospels, nor to institute critical inquiries into the state of the text. Assuming the historical credibility of the Evangelists, his object is to arrange the events which they record in chronological order, and state the grounds of this order. The work is appropriately introduced by three preliminary essays, discussing the dates respectively of the Lord's birth, baptism and death. In selecting the special difficulties in the Gospel narratives which claimed his attention, the author has restricted himself chiefly to those found in the commentaries of Alford and Meyer. Both of these are very able commentaries. The work of Alford clearly takes rank, philologically, above every other English commentary on the entire New Testament, while Meyer stands in the very first class of German expositors. These writers also occupy a somewhat "free position," and while.repudiating most of the objections of the old negative and destructive criticism, they are yet not over fastidious themselves about imputing occasional mistakes to the Evangelists. In restricting himself mainly to the circle of their objections, the author has ensured the noticing of all really serious difficulties, while keeping his pages clear of replies to frivolous and exploded objections.

In the accomplishment of his work the author has been very suc cessful. The list of writers whom he has consulted shows that he has shrunk from no range or labor of inquiry, and that while making no parade of erudition, he has resorted to and faithfully employed all the best sources of information. His style is clear, terse and simple; his discussions are conducted with thoroughness and candor; his conclu

sions judicious, and the whole spirit of the book such as to make it highly serviceable to the student of the New Testament. Though, perhaps, somewhat wanting in definiteness of purpose, it is yet decidedly creditable to American scholarship, and written in hearty sympathy with the spirit of the Evangelists, and the character and teachings of our Lord. It will be found a valuable addition to the works of Ellicott and Westcott.

The Pentateuch Vindicated from the Aspersions of Bishop Colenso.

By WILLIAM HENRY GREEN, Professor in the Theological Seminary, Princeton, N. J. New York. John Wiley. 1863. pp. 195.

Prof. Green has done a good work in exploding, in a terse and vigorous manner, many of the unfounded assumptions and petty cavils of the English Missionary Bishop. He very rightly remarks, that for scholars no refutation of Colenso's book is needed. We might add, that for cultivated and thinking minds, though making no claims to scholarship, it is almost equally unnecessary. The Pentateuch stands in relation to the entire Bible as the system of nature stands in relatiou to the whole system of natural and revealed religion. It is its portico, or rather its foundation, and its necessary condition. Take away the one and you utterly subvert the other. The whole Jewish polity, the whole Jewish history, are rooted in, and rest upon the Pentateuch. Its truth is everywhere assumed, both in the Old and the New Testament. Undermine its authority and not a fragment of the Scripture edifice but crumbles into ruin. David, Isaiah and Jesus Christ, disappear under the touch of the same wand that has struck down the venerable form of Moses. And, we add, that on no part of the Sacred writings is the impress of Divinity more clearly stamped than on that section of them which bears bis name. Yet, to the mass of readers the difficulties, which are insulated, minute and capable of easy exaggeration, are more palpable than the evidences of authenticity, which often depend upon comprehensive intellectual, or high moral surveys. To all these this work of Prof. Green will be of great service. It is written in the right spirit, and does not, like some defences, surrender the stronghold which it professes to defend. It is severely, yet calmly, just to the installed and sanctimonious infidelity of a priestly traitor to the faith, and passes in a very lucid and satisfactory manner over the principal points raised in the bishop's book. It is what it professes to be, a vindication of the Pentateuch from the aspersions of its reverend assailant.

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