178 



NA TURE 



June 23, 1887 



achievement of recent years is the opening of the Canadian 

 Pacific Railway, and the establishment of a line of steamers 

 connecting its we stern terminus with India,China,andJapan. 

 We thusgain a shortened route to the East, passing entirely 

 over great ocean highways and British territory instead 

 of through a land-locked sea and a narrow gut which 

 accident or design may at any moment render impass- 

 able. In view of the expansion of commerce during the 

 last half- century, and of the immense undeveloped 

 resources of Canada, it would be rash to set any limits to 

 the future possibilities of this great Imperial highway. 



" The universal acceleration of locomotion and transit is 

 the most extended and general application of science to 

 the great modern purpose of economizing labour and 

 time. Every department of industry can, however, show 

 special applications for effecting the same result.'' 



ATLANTIC WEATHER CHARTS. 



n^HE Meteorological Council has recently issued the 

 -*■ second part of the Synchronous Weather Charts 

 for the North Atlantic and the adjacent continents, the 

 folio just published embracing two charts for each day 

 from November 8, 1882, to February 14, 1883. The first 

 part was noticed in Nature, vol. xxxv. p. 469, when we 

 gave a somewhat detailed explanation of the charts and 

 the observations upon which they were based. The 

 second part embraces a very large portion of an English 

 winter, and the conditions pictured over the Atlantic show 

 that the weather over that ocean in winter is far more 

 disturbed than it is during the summer months. The 

 barometer in the winter ranges both higher and lower, 

 and the changes of pressure are much more rapid and 

 considerable. The movements of the travelling disturb- 

 ances are also accelerated, and keep in a much lower 

 latitude, the British Islands coming frequently under their 

 full influence after they have passed over the warm and 

 moist air of the North Atlantic. In the summer the 

 barometer is above 30 inches over the greater part of the 

 ocean, but the highest readings seldom exceed 30'3 inches, 

 whilst the areas of low pressure, the readings at the 

 centre of which are seldom especially low, ranging for 

 the most part from 29-2 to 29"5, skirt to the north of the 

 high-pressure area, and pass as a rule well to the north- 

 ward of the United Kingdom. At times these low-pressure 

 areas scarcely influence our weather. At other times, 

 when from some cause the high-pressure area is situated 

 in rather a lower latitude than usual, the low centres will 

 have a more southerly route in their passage from west to 

 east, and will occasion disturbed weather over our islands, 

 but for want of sufficient difference of barometric pressure 

 will but very seldom materially augment the strength of 

 the wind. If, however, this southerly track of the dis- 

 turbances is maintained for any length of time in the 

 summer, it will have a very marked effect upon our 

 weather, occasioning frequent and heavy rains ; it was 

 this which caused the entire failure of real summer 

 weather in 1879. The winter charts show that the baro- 

 meter often ranges as high as 30^5, 30 6, and 307 in 

 Mid- Atlantic, whilst on the adjacent continents such 

 readings are common, and in North America much 

 higher readings occur— on February i tlie mercury 

 reached 31 'i inches. The charts do not extend to 

 Siberia, but it is notorious that excessively high read- 

 ings are commonly experienced there during the winter 

 months. The low-pressure areas which are principally 

 limited to the ocean, and almost solely to the norihern 

 latitudes, frequently have the barometer at the centre 

 below 29 inches, and occasionally below 28 inches. With 

 these differences of barometric pressure there is ample 

 material for the development and maintenance of storm 

 systems ; and the most cursory examination of the charts 

 shows to how great an extent storm after storm rages j 

 almost daily in one part or another of the Atlantic, and j 



frequently several storm areas exist at one and the same 

 time. This second series of charts illustrates in the most 

 unmistakable manner the behaviour of storms over the 

 Atlantic : many a disturbance can be traced in its pro- 

 gress for days together. On November 13 a storm area 

 was passing over the north of France, and was occasion- 

 ing strong easterly gales in the south of England and the 

 English Channel. This disturbance can be traced back 

 day by day until November 3, when it was in the vicinity of 

 the West Indies, where it was apparently bred. The severe 

 storm which was blowing over the British Islands on 

 November 19 was apparently formed over central Nortli 

 America on November 9, and, after travelling slowly over 

 the Lake District, left the Gulf of St. Lawrence on 

 November 14, and followed a north-easteriy track, but, 

 after passing over the south of Greenland, it took a more 

 southerly course, the centre subsequently passing between 

 Iceland and Scotland. A fairly good specimen of storm 

 development is shown on the charts of February 7 and 

 8 : on the 7th, a bend is shown in the isobars of 29^0 and 

 29-1 at about 300 or 400 miles to the west of Ireland, and 

 this on the following day becomes a closed area with its 

 complete wind circulation ; the disturbance, howevei\ 

 dies out again on the 9th. A feature of very speciaJ 

 interest in the charts is the size of some of the disturb- 

 ances : this stands out clearly from the graphic manner 

 of representation. There are many instances of a gale 

 blowing simultaneously in America and Europe, due ti^ 

 the same storm area, and in these cases the area of low- 

 barometer readings usually occupies the whole of the 

 northern part of the Atlantic, whilst over the land, both in 

 Europe and America, the barometric pressure ranges very 

 high. On January 23, as the result of a single low- 

 pressure area, a gale was blowing in Hudson's Bay., 

 Labrador, and Newfoundland, and completely across the 

 Atlantic to the North Sea and the north of Norway, the 

 diameter of the area over which the wind was blowing 

 with gale force, being as much as 3800 miles (nautical) -.. 

 the centre of the storm was situated off the south-wes: 

 coast of Greenland, where the barometer was readini; 

 28'2 inches, whilst in America and Europe the barometer 

 reached 308 inches. An almost equally large disturb 

 ance is shown on February 10, the gale force extending 

 quite across the Atlantic from Labrador and the Gulf of 

 St. Lawrence to the Gulf of Bothnia, the diameter of the 

 gale area being fully 3000 miles. 



The equatorial doldrum is shown to be of less extent 

 than the general charts which have been deduced from 

 averages would lead one to suppose, and very frequently 

 the north-east and south-east trades almost meet. Between 

 longitudes 20° and 30° W., the position atvvhich the trades 

 meet in November is about 5" N., in December about 

 3° N., whilst in January and the early part of February 

 the south-east trade only just blows north of the equ itor. 

 and the doldrum is probably at this time at its most 

 southern limit. The north-east trade is far more regulai 

 on the eastern side of the Atlantic than in mid-ocean 01^ 

 on the western side, and this is fully accounted for by the 

 fact that the wind blows round the Atlantic high-pressure 

 area in agreement with the ordinary anticyclonic circu- 

 lation, so that on the eastern side of this high pressure 

 which is also, as a rule, the eastern side of the Atlantic, 

 the wind is northerly, whereas to the westward of this 

 area of high barometer readings the winds are frequently 

 from the southward. The northern margin of the trade 

 varies considerably, and is almost entirely dependent on 

 the position of the area of high barometer situated over 

 the Atlantic ; when this area is well to the northward the 

 northerly winds hold from the chops of the Channel down 

 the coast of Africa to about 5" N., so that a vessel may 

 leave England and keep a steady northerly and north- 

 easterly wind until close to the equator. 



The winter charts also show that the differences of 

 temperature are much larger over the Atlantic than they 



