cyclone, which lies between the Atlantic and American anticyclones. The latter has moved a little towards the east.

We may give the general features of British weather for these four days as a sample of the type, and the reader may fill up those in any other country for himself. On the morning of the 26th, the weather in Great Britain was wet and broken from the influence of the V. Next day the weather was beautifully fine from the wedge; the third day, wet and stormy-this time from a true cyclone and, finally, cold and fine from the rear of the same cyclone on the fourth day. Similar alternations of weather would go on, with endless modifications, so long as the type persisted. From this we see the contrast which the westerly type presents to the southerly In the latter, Great Britain was constantly exposed to the influence of the fronts only of cyclones; in the former, both fronts and rears develop their characteristic weathers. We gave the details of the changes of temperature which occurred over the whole of Europe during the first three days in our chapter on Heat and Cold.

one.

In this example the United States was constantly under the influence of a persistent anticyclone, and, so far as it goes, this shows the nature of a type of weather in that country.

We can now easily understand the following particulars of the characteristic weather of this type.

The general temperature of this type is about the average of the season-a little warmer in front of the cyclones, and a little colder in rear. In winter, however,

a great prevalence of this type gives an open season, as the high wind prevents frost, unless the cyclones are so far north that the influence of the Atlantic anticyclone is felt.

In summer, on the contrary, if the type be intense, the temperature is below the average, from the excess of cloud hiding the sun.

Another important consideration, as regards temperature, depends on the position of the normal cyclone-path. The difference of temperature just north and south of a cyclone-centre is very marked, so that when cyclones pass further south than usual, the temperature of the region lying between the usual and actual paths is greatly lowered.

To this type also belongs a peculiar class of warm, cloudy anticyclones, which seem to be associated with cyclones passing to the far north, but which have not yet been investigated.

As regards damp, wind, and weather, the most noticeable feature of this type is the changeableness of all these elements. This must be so, because the rapidly moving cyclones bring up alternately the damp, rainy, southerly winds and the dry, cold, northerly currents of their fronts and rears respectively.

The telegraphic forecaster, instead of thinking how cyclones are going to die out, as in the southerly types, has to consider along what paths they will move. No generalities are of much assistance; his opinion must be formed by his own judgment, and from experience of cyclone-paths in his own country. For instance, in Great Britain, he can often tell whether the centre will skirt

the north-west coasts of Scotland, or else traverse England on its way to Denmark.

Dr. J. van Bebber has classified the cyclone-paths of Central Europe for the use of the Deutsche Seewarte, while in the United States they know that the great majority of cyclone-paths pass along the line of the Lakes and St. Lawrence valley. But, in spite of any classification, we must never forget that a cyclone may travel in nearly any direction, and for that reason the knowledge of the most usual paths is of less use in forecasting than in explaining the climatic peculiarities of a country.

NORTHERLY TYPE.

The special feature of this type is the presence of a large anticyclone over Greenland and the arctic portion of the Atlantic, which either joins the Atlantic anticyclone or is only separated from it by a col. On the east side of this, over Europe and Russia, lies a persistent area of low pressure, which is the theatre of the formation of an incessant series of cyclones, while innumerable secondaries are formed over Great Britain and France. The cyclones either move eastwards, or else, if they stand still, surge up and down and alter their shape in a very peculiar manner.

This is, in fact, the exact converse of the southerly type. In that, Europe was persistently under the influence of southerly winds and cyclone-fronts; in this, it is as steadily under the influence of northerly winds and cyclone-rears.

This type occurs chiefly in the winter, spring, and summer; it is very rare in the autumn months.

On the American side of the Atlantic, this distribution of pressure exercises a profound influence on the general character of the weather. Instead of the cyclones finding an easy path into the Atlantic, their eastward progress

FIG. 72.-Northerly type of weather.

is checked by the areas of high pressure, and in some instances their direction is even reversed.

For instance, in Figs. 72-75 we give reductions from the United States maps of the northern hemisphere, for March 22 to 25, 1878, at 0.43 p.m. Greenwich, or 7.35 a.m. Washington time. In all the Atlantic high pressure

will be found stretching far north, till it nearly meets another anticyclone lying over Greenland; and in all, relatively low pressure will be found both over Northern Europe and the western states of the American Union.

On March 22 (Fig. 72), each of these low areas contains a cyclone, one over Finland, giving northerly winds

FIG. 73.-Northerly type of weather.

and cloudy weather over Great Britain and the greater part of Europe; the other about three hundred miles west of Newfoundland. An independent cyclone lies near Florida, and a col separates the Atlantic and Greenland anticyclones.

By next day (Fig. 73), though the centre of the