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of depth down to 800 fathoms, at which the thermometer stood at about 499. But within the next 200 fathoms there was a sudden reduction of no less than nine degrees, the thermometer at 1,000 fathoms standing at 40°, and gradually falling at still greater depths to about 36° 5', which seems to be the temperature of the whole mass of water occupying the deeper part of the North Atlantic basin.
Thus it seems obvious that this deeper stratum, as the Physical theory already stated (p. 592) would lead us to predicate, mainly consists of water that has flowed southwards from the deeper part of the Arctic basin, carrying with it the low temperature it has there derived from exposure to surface-cold. And it is an additional confirmation of this view, that a large number of northern Mollusks, Crustacea, and Echinoderms were obtained from the bottom over which this deeper stratum is diffused. It is further obvious that this low bottom-temperature could not be permanently maintained, unless there were a continually-renewed supply of Polar water; and this renewal can only be effected by a gradual movement of this stratum from the Polar towards the Equatorial area, as in the experiment already described. As it proceeds onwards, the upper portion of it will be continually receiving an accession of heat from contact with the warmer water above, and will be, so to speak, absorbed into the upper stratum through the “stratum of intermixture;” so that we might expect that, as we pass towards the Equator, the cold stratum will lie deeper and deeper, whilst in passing towards the Pole it will come nearer and nearer the surface, which the temperature-soundings recently taken show to be the case. Thus in the neighbourhood of the Faroe Islands, we found the influence of the deeper Arctic flow beginning to make itself distinctly perceptible in the reduction of the temperature at depths exceeding 500 fathoms; but this reduction, beginning sooner, takes place more gradually, so that there is not the same distinct “ stratum of intermixture” that we met with at the southernmost part of our survey.
On the other hand, it appears from a comparison of the temperatures taken down to 800 fathoms in the Porcupine expeditions of 1869 and 1870, that there is a slow northward movement of this upper warm layer from the coast of Spain and Portugal to the Faroe Islands, its surface-temperature suffering a considerable reduction (from 69° to 49), while at depths of from 100 to 500 fathoms the reduction is not more than from 50 to 6o. Consequently, while the temperature of this stratum off the coast of Portugal is rather below than above what may be considered the normal of its latitude, it is very much higher than the normal in the latitude of the Faroe Islands, the climate of which is greatly ameliorated by it.
In the deep channel between the Faroe and the Shetland Islands, we found a sort of compressed epitome of the Oceanic vertical
circulation, which was extremely remarkable. The upper part of this channel, in which the bottom lies at a depth of from 600 to 700 fathoms, is occupied by the warm stratum just described, of which the temperature gradually descends from an average of 52° at the surface to 45° at 200 fathoms; but in the next 100 fathoms-constituting the “stratum of intermixture”—there is a reduction of 13°, bringing down the temperature to the freezing-point of fresh water at 300 fathoms, beneath which depth it sinks still further. And the whole under-stratum, exceeding 300 fathoms, or nearly 2,000 feet in depth, thus forms an Arctic stream having a temperature below 30°, and bringing with it the characteristic animals of Iceland, Greenland, and Spitzbergen. This stream is one of the “feeders” of the deep glacial stratum of the Atlantic ; and it can scarcely be doubted that further inquiry will bring to light the existence of similar feeders elsewhere. On the other hand, the comparatively warm stratum by which it is overlaid, slowly moving in a north-easterly direction, goes to keep up the surface-level and to ameliorate the climate of the Polar area; taking the place of the previous arrival, which, after having been cooled down and having sunk to the bottom, has gone forth as a glacial underflow.
It may, then, be fairly claimed for the doctrine of the slow Polar equatorial movement of the deep glacial stratum, and of the slow Equatorial polar flow of the upper and warmer layer of Oceanic water, dependent upon difference of Temperature alone, that it is in harmony alike with Physical theory and with the facts of observation. That the warm stratum in the neighbourhood of the Faroe Islands very commonly extends to a depth of 500 or 600 fathoms, seems conclusive evidence of its non-derivation from the Gulf stream ; since, where this can be last traced as a definite surface-current, its depth is less than 50 fathoms. And it is obvious that the vast body of water of which this warm stratum consists must be far more effective in the transportation of heat, than such a mere surface-film. For, as we have seen, whilst the superficial layer of this warm stratum loses 20° between Lisbon and the Faroe Islands, the layer beneath, to the depth of 400 fathoms, loses only about 5o.
If, then, our doctrine of a general Oceanic vertical circulation be true, this Pole-ward movement of the upper warm stratum of the North-Eastern Atlantic would go on just as usual, even though the Gulf stream were to-morrow to be diverted into the Pacific; and all that we should lose would be a certain portion of the warmth of the south-westerly winds, which originate in the true Gulf stream area. Those of us who prefer a bracing frosty winter to the “green Yule” which is said to make a “fat kirkyard,” might not regret the change.
W. B. CARPENTER.
SICK TRANSPORT AND VOLUNTEER AID
throes of anxiety respecting our military defences. We are deliberating on the efficiency, or inefficiency, of our artillery, on our supply of powder, on the possibility of filling up the cadres, or skeleton corps, of our regiments with reserves of trained men; in short, we are puzzling out the best way of bringing our military resources generally into a position to cope with the armies of the Continent; and with two millions of young men capable of military service, Great Britain needs but the will to find the way. It may thus be worth while to devote a little consideration to a department of military service of which the importance is far greater than is commonly supposed; for its imperfection has caused terrible loss and suffering to be habitual in English military expeditions, and has times out of number changed the fortune of a campaign or even of a war. I mean the provision for treating and the transport of the sick who encumber every military force.
Since the disasters of the Crimean War the Government has done much to meet well-known requirements in this respect. But our difficulty lies in that parsimony in military expenditure demanded by the nation, who, in the intervals of peace, is more eager to cut down taxes than to maintain the national defences. Hence, those preparations which can be properly carried out only in the leisure of peace are stinted or neglected outright. This habit is disastrous. The
nation cannot learn too soon that in war, as in every other craft, success comes, not through good luck, but just so much as we are skilled and ready in every detail. The transport of the sick and wounded of British forces, when compared with that of other armies, is lamentably deficient in important respects. That it remains so, in spite of the recommendations of commissions and committees of military men appointed to inquire into the question, can only be attributed to popular apathy. The public can comprehend that soldiers are necessary, that guns and powder are indispensable, but it is in profound ignorance that the loss by sickness from the effective strength is always far beyond that of the killed and wounded in battle. The chief danger to the soldier lies in the exposure, fatigues, and privations incident to his vocation. Of the British army in the Crimean War, 16,211 men died of sickness, but only 4,595 were killed in the field or died of their wounds. These privations, moreover, while susceptible of much diminution through due care and forethought, are increased in a far greater ratio by neglect of simple and well-known laws of health. Examples are plentiful in the histories of all wars of the importance of keeping down and disembarrassing an army of its sick. In the Peninsular War, 22; per cent. of Wellington's fighting strength was always in hospital. In Napier's history we are constantly being reminded how greatly Wellington's tactics were affected by the necessity for securing the safety and removal of the sick to the base of operations. This labour was performed in the rough bullock-carts of the country; and the difficulty of providing transport of even this rude description with sufficient rapidity to prevent over-crowding in the temporary hospitals was a constant anxiety to Sir James McGrigor, the chief medical officer to Wellington's army. It is well known that the delay after the battle of the Alma, caused by lack of proper means for collecting the wounded of the British army, was most precious to the Russians. Had the Allies at once advanced on Sebastopol, no serious resistance could have been opposed to their entry of that fortified arsenal. But it was impossible to leave the wounded on the field of battle, and two days were spent in carrying them on board the transports off shore—a task, indeed, only accomplished with the aid of the seamen of the fleet, and of the mule litters lent by the French. When the British landed in the Crimea, the sole means of transport for the wounded consisted of one baggage pony and ten stretchers per regiment, besides six arabas, or country carts, picked up during the march from Old Fort to the Alma, to carry those who were attacked with cholera. Thus we find the Sanitary Commission, which was sent to the Crimea in 1855, stating that men had died for want of means to carry those who fell ill on the march. In all
die on the field for want of immediate succour; the wounded of the vanquished being of course the last to receive attention. General Fay, of the French army, has related how, three days after the assault of the 8th September, 1855, he found French and Russians lying one against another, or against the rotting bodies of those already dead, having been starving since they fell. Again, Chenu tells us that after Inkerman, though, thanks to the French Transport Corps, all our own wounded were safely housed by ten at night of that terrible day, over 500 Russians lay the whole November night where they fell, some even were not found for a week after the battle. Occurrences as terrible have happened after the battles of the siege of Paris and in those of the Orléannois. But in summer the same may come about. M. Dunant, in his “Souvenir de Solferino,” describes the consequences of insufficient preparation for the wounded after that battle. The little town of Castiglione, twice already the scene of French victory over the Austrians, was crowded with wounded of all nations, French, Italians, Arabs, Germans, Bohemians, Hungarians, and Croats. The churches and public buildings being full, straw was laid along the streets; on this the wounded were placed, sheltered from the fierce sun by boards or awnings stretched from house to house. Numbers died on the battlefield ere they could be moved to any shelter at all. In consequence of the rapidity with which Montebello, Magenta, and Solferino followed each other, the towns, and even the larger cities of Northern Italy, were crowded with patients. Brescia had over 32,000 sick added to its usual population of 40,000 during the summer of 1859. But the early stages of the American War give perhaps the most startling instances of the horrible loss that ensues if transport be not at hand to gather and distribute the wounded. At the battle of Manassas, or Bull Run, August 30, 1862, 2,000 wounded lay on the field from Saturday to Wednesday without food or water. At Antietam even, though later in the war, it is officially estimated that at least 500 lives were lost through want of means to convey
the wounded to hospital.
These examples suffice to indicate what frightful suffering follows a hard-fought action, if the sick transport be not duly organized before war is entered upon. Next, to discuss the amount of transport probably requisite for an expeditionary force. Sick transport for military forces is of two kinds : first, that which accompanies the moving columns, collects the wounded in battle, and tends them in the temporary field hospitals; second, that which clears away the wounded and sick from these crowded receptacles, and distributes them into the permanent or reserve hospitals established at the base of operations, or at home. To consider the first. In decisive con