Thus, on an average of years, there are 24.12 days of north wind in Sandgate, 24:46 in Undercliff, 62:50 in Hastings; of north-east, 45 80 in Sandgate, 54:61 in Undercliff, 43 50 in Hastings; of east, 37-69 in Sandgate, 60 34 in the Undercliff, 34 50 in Hastings; of south-east, 33 24 in Sandgate, 1885 in the Undercliff, 15.50 in Hastings; of south, 27.53 in Sandgate, 26.72 in Undercliff, 17 in Hastings; of southwest, 75.31 in Sandgate, 96 97 in the Undercliff, 137.50 in Hastings; of west, 65.29 in Sandgate, 52.24 in Undercliff, 28 in Hastings; of north-west, 56.35 in Sandgate, 30.95 in the Undercliff, 12 in Hastings.

The character of the prevailing winds is a matter of the utmost importance to the invalid. We are all, naturally, provided with a sort of barometrical apparatus in our sensations as the electrical conditions and the height of the atmosphere vary, and those sensations become more acute when we suffer from disease or advance in years. It is curious, but demonstrable notwithstanding, that the period during which the cold winds prevail is the very time when they can best be borne. Influenced by the heat of the sun, and by the warmth of the surface over which they sweep in summer, even the northerly and easterly winds are deprived of their sting in the vicinity of this coast, though in spring and late autumn their presence is at once recognisable by the harshness of the air. The north-east wind of March or November is a very different thing from the wind of the same origin blowing in July or August.

Thus it is evident that we are favoured with a prevalence of warm winds in winter and spring, while the southern breezes, tempered by passing over many miles of sea, refresh us in the heat of summer; for though it is true that the ocean is several degrees higher in temperature than our atmosphere in the winter months, it becomes below the temperature of the air in summer.

In the general temperatures of the town we find a high annual mean and gradual alternations.

From the rising to the setting of the sun the greater portion of its winter rays fall on the town, and it must be admitted that in summer the heat would be very great were it not tempered by the shade afforded by trees and houses, by the cooling influence of the sea breezes, which, as I have shown, prevail when they are most needed, and by the ocean itself. We have something like the tropical evening breeze, which sets along the shores of the West Indian islands to prevent the depressing effects of a hot atmosphere. In winter, the sun's rays falling on the surface of the cliff communicate to it a temperature comparatively high, and the caloric absorbed by the rocks, and communicated from the surface of the cliffs to the town, is felt long after the summer has passed away, and moderates the intensity of the coldest days, which are, however, higher in temperature, as I shall demonstrate hereafter, than the coldest days of most other places on the coast.

Temperature is, we all know, derived from the one

great source of light and heat-the sun; in towns, there is an appreciable ingredient in the temperature created by artificial fires. To repeat the most rudimentary principles of science, I may remark, that the heat of any given quantity of air depends on its specific gravity-and that its specific gravity is greatest at the level of the sea. If we test the temperature of equal weights of air taken from the level of the sea and from a place considerably above it, and evolve the caloric, we find the quantity of heat the same in both, but the sea air will feel warm, while the land air will feel cool. This explains the reason why the high air of the mountain is seemingly colder than the air of the valley. The air is as warm above as the air below, but there is less of it; and, properly speaking, the cold of high mountains arises from want of air; its extreme rarification, and not from any want of caloric in the air itself. It is evident that besides these conditions, which are dependent on the atmospheric pressure, that-speaking generally and without reference to exceptional cases-the air which is most dense is fittest for delicate organs, as it contains the greatest proportion of the vital gas -oxygen-which is introduced into the system with the same ease as in the thinner air, the only difference being, that the object is effected much more rapidly in the latter case than in the former.

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"The proper, constant, and inexhaustible sources of oxygen," says Liebig, are the tropics and warm climates; where a sky, seldom clouded, permits the

glowing rays of the sun to shine upon an immeasurably luxuriant vegetation. In our winter, when artificial warmth must replace deficient heat of the sun, carbonic acid is produced in super-abundance, and is expended in the nourishment of tropical plants. The great stream of air, which is occasioned by the heating of the equatorial regions and by the revolution of the earth, carries with it, in its passage to the equator, the carbonic acid generated during our winters; and in its return to the polar regions brings with it the oxygen produced by the tropical vegetation."*

It is almost assuming too much to take for granted that every one is acquainted with the conditions on which the great animal function-" Respiration"— depends. At all events it may not be out of place to add a few remarks, which demonstrate the uses of an abundant supply of oxygen.

The atmospheric air, when it goes into the lungs, is composed of about four parts of a gas called nitrogen, and one part of another gas called oxygen.+ But the air which comes out from the lungs is not the same in composition, for a considerable quantity of oxygen is found to have disappeared, and in its stead we find another gas, called carbonic acid, which is produced by the union of a portion of oxygen with the carbon which forms a large ingredient in the

* Agricultural Chemistry, p. 19.

We omit mention of the small quantity of carbonic acid in the air.

composition of the blood and of the body in general. Carbonic acid is a gas which is fatal to animal life, and it is therefore discharged from the lungs. If an animal is made to inhale it, insensibility and death follow in a very few minutes. It has been established that the venous blood is a poison to the animal body, and it is probably this same carbon, or the carbonic acid, that makes it noxious. It appears that about 45,000 cubic inches of oxygen are consumed by an ordinary man in twenty-four hours, and that 40,000 inches of this gas go to form the carbonic acid produced during the same period, the remainder of the oxygen probably combining with other ingredients of the blood. Under different circumstances, however, the consumption of oxygen varies. It is considerably greater when the temperature is low than when it is high, and during digestion the consumption has been found one-half greater than when the stomach is empty. By violent exercise, when the stomach is empty, it has been found to be augmented to three times its usual quantity, and to four times its usual quantity when food has been taken after this.

When we thus see the great quantity of pure atmospheric air which a single individual requires to carry off the noxious parts of the venous blood, and to convert this into arterial blood, we can easily comprehend why such dreadful consequences should follow the breathing of a highly vitiated atmosphere. The most melancholy instance of this kind on record, is the well-known one that occurred in the Black

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