August 7, i! 



NA TURE 



33/ 



ruary 2, 1884. During these months the extremes at 

 Fort William were ~y'S and 27°-o. 



The barometric observations at Fort William and lien 

 Nevis were dealt with in a similar manner, and a table of 

 corrections of the Ben Nevis observations to sea-level 

 was constructed directly from the observations of the two 

 stations, the table giving the approximate corrections for 

 each tenth of an inch of the sea-level pressure, and for 

 each degree of mean temperature of the stratum of air 

 from the Observatory to sea-level, which was assumed to 

 be the arithmetic mean of the temperatures at the two 

 stations. The normals of atmospheric pressure for Ben 

 Nevis were then calculated. The lowest normal monthly 

 pressure is 25T41 inches for January, and the highest 

 25'4io inches for June, and for the year 25'2Si inches. 

 Comparing the normal pressures at the high- and low- 

 level stations, pressure on Ben Nevis is on the mean of 

 the year 4-557 inches lower than at the sea-level at Fort 

 William, the least monthly difference being 4484 inches 

 in July, and the greatest 4^620 inches in February. 



The morning maximum of pressure was at 10 a.m. in 

 January, at noon in February and March, 1.30 p.m. in 

 April and May, while in June it was delayed to 3 p.m. 

 From Mr. Wragge's observations in 1882, the same diurnal 

 phase of the pressure occurred about 9 a.m. in the summer 

 months at Fort William, being thus six hours earlier than 

 on the top of Ben Nevis. From February to June the 

 morning minimum of pressure was very large. On the 

 other hand, the afternoon minimum was comparatively 

 small ; and as the season advanced it became less and less 

 pronounced, till in June the diurnal oscillation approached 

 closely to one single minimum and maximum. Owing to 

 the low readings of the morning minimum and the high 

 readings of the afternoon maximum, which have their 

 explanation in the diurnal change of the temperatureof the 

 aerial stratum below the level of the Observatory, the 

 diurnal range of pressure on Ben Nevis exceeds that of 

 any other meteorological station in Scotland. 



The rainfall on the top of Ben Nevis is very large. At 

 Fort William the mean annual amount is about 83 inches. 

 During the three years beginning 1881, while the rainfall 

 at Fort William was 24-59 inches from June to October, it 

 was 47'lo inches on Ben Nevis. During the two years 

 1882 and 18S3, for the same months, the rainfall at Fort 

 William was 21-96 inches ; at the lake (1S40 feet high), 

 28-42 inches ; but on Ben Nevis, 44-35 inches : hence 

 during the summer months the rainfall on Ben Nevis is 

 nearly double that of Fort William, and the greater part 

 of the increase in the rainfall from Fort William to the 

 top of Ben Nevis takes place above the level of the lake. 

 No inconsiderable proportion of the large rainfall collected 

 on the top is due to driving mists and drifting wet fogs, 

 during which, though often no raindrops are visible, or only 

 a few small drops at wide intervals apart, yet everything is 

 dripping wet, and the funnel of the rain-gauge is crowded 

 with numerous runnels of clear water, steadily trickling 

 down into the receiver of the gauge. 



On plains and extensive plateaux the wind attains a 

 diurnal maximum velocity shortly after noon which is 

 generally nearly double the minimum velocity, which 

 occurs shortly before sunrise. But on Ben Nevis, in 

 common with other observatories which are situated on 

 peaks rising to a considerable height above the whole of 

 the surrounding region, the reverse of this takes place, 

 the maximum velocity occurring during the night, and 

 the minimum during the day. The difference between 

 the mean minimum and maximum hourly velocities on 

 Ben Nevis in each of the seven months ending June last 

 was about five miles. A tendency to a secondary maxi- 

 mum was shown in May, but in March, April, and June 

 no such tendency was apparent. A full gale from south- 

 cast blew almost continuously at the Observatory from 

 February 15 to 21, and during these seven days there was 

 a mean maximum of 58 miles from 5 to 6 a.m. and a 



mean minimum of 42 miles from 4 to 5 p.m. With an 

 hourly difference of 16 miles, the daily variation in the 

 velocity of the wind was maintained during the continu- 

 ance of this great storm. 



Another main object in constructing the table of cor- 

 rections to sea-level for Ben Nevis Observatory was to 

 afford a ready comparison between the atmospheric pres- 

 sure at sea-level and that on Ben Nevis from the im- 

 portant bearings of the observed differences on the 

 changes of weather which precede, accompany, and 

 follow storms, and on such inquiries as the singular and 

 opposite relations which obtain during storms of wind 

 and during the remarkable weather which often occurs 

 within, or on the confines of, anticyclones. 



Al.F.X WhI.K BUCHAN 



THE FORESTRY EXHIBITION 



CINCE our last notice of the International Forestry 

 •--' Exhibition great progress has been made in the 

 concentration and arrangement of the various products 

 which testify to the importance of the subject. We be- 

 lieve that the juries have now met, and such names as 

 Sir Joseph Hooker, Colonel Moncreiff, R.A., Profs. T. R. 

 Fraser of Edinburgh, Bayley Balfour of Oxford, Dr. Lyons. 

 M.P., with several Indian and Scotch Forest Officials, 

 and others will inspire confidence in their work. We 

 to-day give a description of one of the most interesting 

 sections, which well repays a visit. 



The Japanese Court occupies the eastern transept, and 

 forms one of the largest and most important sections. 

 The whole arrangements have been carried out in the 

 most thorough and business-like manner. Immediately 

 011 the arrival of their goods, knowing beforehand the 

 amount of space required, and working with a rapidity and 

 skill which might put to shame some more civilised nations, 

 the Japanese Commissioners have shown that they are 

 far in advance of many countries in business capacity as 

 well as in the science of forestry. In Great Britain the 

 importance of forestry to the welfare of the country and 

 its colonies has but lately been recognised. In Japan, 

 on the contrary, it has long formed an important feature 

 in national education. This is evident from the ingenious 

 devices represented on the walls of the department, 

 and which can only have been the outcome of long 

 experience. 



With excellent taste the Japanese have placed the tim- 

 ber in the most prominent position, and the products in 

 the background, giving at once the impression that it is 

 purely a forestry exhibit. The central tables are occu- 

 pied with longitudinal sections of trees, with the surface 

 planed so as to render the grain visible. Above these 

 are similar sections, but showing the bark, and above 

 these are coloured drawings of the trees yielding them. 

 At the foot of these sections a paper explains in English 

 the Japanese name, the botanical name and habitat, and 

 the relative rarity or abundance of the tree, its girth and 

 height at fifty years old and at maturity, the best mode 

 of propagation, the quality and uses of its wood and of 

 other parts. Each section, drawing, and description is 

 marked with a corresponding number. On the wall of 

 the Southern Court are some artistic drawings in mono- 

 chrome of the various devices for felling and floating the 

 trees along mountain streams, for slipping them over pre- 

 cipitous cliffs, and for stopping and collecting the timber 

 at certain localities in its course for storage. The expe- 

 dients adopted for floating the timber down narrow gullies, 

 and the sledges used for sliding it down over the snow in 

 winter, and other details of forest work and a forester'- 

 life, are depicted in a manner that is easy to remember 

 from the quaint dress, the life-like attitude, and excessive 

 energy thrown into the actions represented. These draw- 

 ings are mounted in wooden frames, and the background 



