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the cadets of which have been sent for training to the continental schools of forestry. The present volume is the outcome of the first five years' results obtained at the stations in Bavaria established under the superintendence of Prof. Ebermayer, of the Forest School of Aschaffenburg.

Many of the statements in the book depend on the observations of only three years, or even of a single year, but our author states his conviction that the main features of the subject can be elicited with sufficient accuracy for each station in a period of observation as short as that mentioned, and that the instrument can then with advantage be removed to a fresh station.

It must be remembered that the difficulties of the observations are very exceptional, as the mounting a ladder to read a thermometer in the top of a tree is not an agreeable duty to perform in all weathers, and so too great a tax must not be laid upon the officials to whom the instruments are entrusted.

The subjects investigated in the open country are, speaking generally, temperature in shade and sun, earth temperature, hygrometry, rainfall and evaporation. To these are added, in the forest, observations made in the head of the tree and on the temperature of the heart of the tree itself at various heights.

The first stations were established in 1867, and the total number in Bavaria is seven, distributed over the country. To these is added one in Bohemia on the property of a nobleman. The outfit of each station cost about £40, and the yearly cost of maintenance is one-half that sum. Some of the apparatus used deserves special notice, especially the vaporimeters for open water surfaces and for soil, and the arrangements for determining the amount of infiltrated water.

The subject is, comparatively speaking, so new and the variety of observations so great that the author for the most part contents himself with simply enumerating his results without attempting to deal with the subject as a whole. We shall therefore confine our remarks to an account of some of the more important subjects touched upon in the volume.

Earth Temperature comes first, as being the most important element for vegetable life. It is found at the various depths, 0-4 feet, to be lower, to the extent of twenty-one per cent., on the mean of the year, in the forest than in the open, and this is pre-eminently the case in

spring and summer, while in winter the difference is scarcely traceable. This shows us that the effect of clearings is mainly felt in summer, and that it is greater the warmer is the climate. Diurnal range is felt only to the depth of three feet, and it is materially diminished by the presence of forest. The annual range of temperature is less in the forest than outside it, but the periods of the two phenomena do not agree very closely.

The effect of wood on Air Temperature is similar to that just described, but the extent of the influence is only about half that exerted on earth temperature: the differences between the temperature above and underground thereby produced are of great importance as affecting the aëration of the soil, and thereby the nutrition of the roots. The observations as regards height show furthermore that the temperature rises with the height at least up to the level of thirty or forty feet. When we remember that the diurnal range is reduced by the presence of wood we see how an alternatihg vertical circulation, like that assigned as a cause for land and sea breezes, is set on foot, the existence of which, as our author amusingly states, may be proved by watching the smoke of a cigar.

The tendency of forests is found to be to moderate the extremes of temperature, and so to render the climate less severe. This is a direct contradiction to the popu lar idea that the cutting away of our forests has made our climate less extreme than it used to be.

The observations on Tree Temperature are very valuable, as by them we are able to determine far more simply than by any other means the total amount of heat required by each tree for its development. These experiments also throw great light on the causes which regulate the flow of the sap.

Becquerel's idea that trees warm the air is distinctly controverted by the results under discussion, which show that the temperature of the trees themselves is generally below that of the air.

In the winter the trees are colder than the soil, and in summer warmer: hence we see that the main seat of activity is in the roots in winter and in the branches in summer.

As concerns Vapour Prof. Ebermayer finds that the existence of timber produces no difference in the absolute quantity present in the air, but that owing to the depression of temperature the Fraction of Saturation is raised by the forest.

Evaporation from a free water surface is to the contour of the country itself. The about sixty-four per cent. less in the for- influence of forests on rain is however est than in the open, and morever it is much greater among mountains than in far more ruled by the motion of the air the plains; it is also greater in hot clithan by the temperature. Hence we see mates than in cold, and in summer than the importance to young plantations which in winter. are likely to suffer from drought of leav- The actual amount of rain which is coling belts of trees to shelter them. Any-lected on the ground in a forest is about thing which breaks the force of the wind three quarters of that which falls on the retains moisture in the soil. cleared land outside. The quantity in The evaporation from the soil is, how-defect does not all remain in the tree ever, a very different thing from that from a free water surface, and in considering it we arrive at the valuable result that the brushwood, leaves, &c., which cover the ground exert quite as great an influence in retarding it as the forest itself.

It is found that for every hundred cubic inches of water evaporated from the soil, in the open, the ground in a forest, cleared of brushwood, &c., gives off only thirty-eight, and the uncleared ground, in its natural condition, give off only fifteen cubic inches. Hence we see how immediately the water supply depends on the wood, and the fact confirms the old observation that in new and thriving settlements the springs dry up in proportion as the land is cleared.

tops, as much runs down the stem; but it is found that the proportion retained by the foliage differs with the different character of the wood; thus it is greater with conifers (Nadelholz) than with leaf trees (Laubholz), and of all trees Scotch fir retains the most.

The usual proportion between evaporation from a free water surface and rainfall on the same surface during the year is that the former rather exceeds the latter. The evaporation from the ground is very different from that from a water surface, and so, as regards the soil of a wood, the proportion above mentioned is reversed, for the diminution of evaporation is less than that of rainfall. If however the wood be cleared of brushwood, leaves, &c., the rate of evaporation from the soil is seriously increased, and in fact in such a case the amount of water stored up in the ground against periods of drought falls below that in open land, owing to the fact that so much of the rain is intercepted before it reaches the ground.

It is a self-evident proposition that plants require rain, but Hellriegel has shown how much they require: according to him every pound of barley requires the supply of seven hundred lbs. of water during the period it is in the ground. Trees require a different quantity from corn, and in addition they have a very great effect in draining the land, for it is The work concludes with some refound that land from off which the tim- marks on ozone, and on the hygienic efber has been entirely felled often becomes fects of forests, and with some practical swampy, and only dries again when the applications of the results obtained to the new plantations spring up. This fact explanation of the causes of certain disshows us that trees exert a constant de- eases which are very destructive to young mand on the moisture of the soil, so that fir plantations. Copious tables are apover-drainage of the ground must seri-pended, with an atlas of graphical repreously affect their growth. sentations of the results.

It is then a most important matter to Our hearty thanks are due to Prof. determine the effect of forest on moisture. | Ebermayer for the work, which contains, Prof. Ebermayer's experiments lead him as will be seen, a mass of carefully colto the view that the idea of the effect usu- | lected and important data of the highest ally attributed to wood in increasing rain- value to the scientific meteorologist and fall is not fully justified, and that much botanist, as well as to the practical for which has been held to be due to the tim- ester and the landscape gardener. ber in a country is really much more due]

GENERAL LEFROY, the Governor of Bermuda, well known as a scientific man during his long service at the War Office, has published a very admirable report on the sanitary condition of Bermuda, compiled with the special objects of gathering information respecting the recent visits of yellow fever to that colony, and of studying the general effects of the climate on the European and African races. These meet, we may observe, at Bermuda under fairer conditions than in any other British possession, the climate being temperate without being cold for nearly half the year, though of tropical heat during the summer. Thus favoured, however, Bermuda, even independently of the dreaded epidemic, stands at present lower as to health results than the actually tropical stations of our troops in the Windward and Leeward Islands, though much higher than Jamaica. General Lefroy's report does not appear to settle the important question as to whether the fever which ravaged the garrison in 1843, 1853, 1856, and 1864 can be traced to direct importation; but it is abundantly shown that the absence of all proper drainage precautions, added to certain cases of overcrowding, had established before each recurrence conditions abundantly favourable to the propagation of the malady when once fairly started. General Lefroy, in summing up his results, gives it as his opinion that to protect the islands effectually the sanitary measures urgently needed should be supplemented by a moderate system of quarantine, to be enforced, however, only during the hot or dangerous months. With regard to the general effect of the climate, it is apparent that, though relaxing to the young, it is very favourable to the advanced in years. The report gives a total of persons dying at ages over seventy-five years, which General Lefroy remarks "could probably not be matched by any district of 12,000 souls in England. It would have gladdened the late Sir George Lewis, however, to learn that the alleged cases of centenarians, of which four were at first reported to the governor, proved on close inquiry to be as mythical as many others nearer home, the oldest, a white lady, having died when still wanting three months of the hundred years.

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Pall Mall.

That which is most pure in man is most divine "Blessed are the pure in heart, for they shall see God." That which is most tender in God is most human :- "Like as a father pitieth his children, so the Lord pitieth them that fear Him."

These two rays of light meet in Christ. Do they neutralize each other as light beams sometimes do? Does the divine weaken the human? the pure diminish the tender? The reverse. It is sin that hardens and dehumanizes us. So, then, with what confidence we may cast ourselves on a sinless Saviour, "holy and yet harmless!" Thoughts by the Way.

"LOST WITH ALL HANDS." "LOST, with all hands, at sea." The Christmas sun shines down On the headlands that frown o'er the harbour wide,

On the cottages, thick on the long quay side, On the roofs of the busy town.

"Lost, with all hands, at sea." The dread words sound like a wail, The song of the waits, and the clash of the bells,

Ring like death-bed dirges, or funeral knells, In the pauses of the gale.

Never a home so poor,

But it brightens for good Yule-tide.
Never a heart too sad or too lone,
But the holy Christmas mirth 'twill own,
And his welcome will provide.
Where the sea-coal fire leaps,
on the fisherman's quiet hearth,
The Yule log lies, for his hand to heave,
In the flush of his strength and mirth.
When he hastes to his bride on Christmas Eve,
High on the little shelf
The tall Yule candle stands,
For the ship is due ere the Christmas night,
And it waits, to be duly set alight
By the coming father's hands.
Long has the widow spared

Her pittance for warmth and bread.
That her sailor boy, when he home returns
May joy, that her fire so brightly burns,
Her board is so amply spread.

The sharp reef moans and moans.
The foam on the sand lies hoar;
The "sea-dog" flickers across the sky,
The north wind whistles, shrill and high,
'Mid the breakers' ominous roar.

Out on the great pier-head,
The grey-haired sailors stand,
While the black clouds pile away in the west,
And the spray flies free from the billows' crest,
Ere they dash on the hollow sand.
Never a sail to be seen,

On the long grim tossing swell,

Only drifting wreckage of canvass and spar,
That sweep with the waves o'er the harbour
Their terrible tale to tell.
bar,

Did a vision of Christmas pass
Before the drowning eyes,
When 'mid rent of rigging and crash of mast,
The brave ship, smote by the mighty blast,
Went down 'neath the pitiless skies?

No Christmas joy I ween,
On the rock-bound coast may be.
Put token and custom of Yule away,
While widows and orphans weep and pray
For the "hands, lost out at sea.'

All The Year Round.

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