X PREFACE. 



have been extended and others begun and partly carried out. In the Appendix to this 

 volume (p. 447) will be found summaries of several papers that have appeared in the 

 publications of the Royal Society of Edinburgh and the Scottish Meteorological Society, 

 as well as papers specially written for this volume. The subjects treated of in these papers 

 include preliminary discussions of changes connected with Fine and Cloudy Weather, and 

 a, report on the observations of Atmospheric Dust, including, in each case, not only the 

 results at the Ben Nevis and Fort- William Observatories, but also observations at other 

 places. There are also several papers on the relations of Barometric Pressure and 

 Temperature at the two Observatories, and the reduction to sea-level of the Ben Nevis 

 barometer readings. This latter subject is one that opens up a most promising 

 investigation as regards the question of the reduction to sea-level of barometric 

 readings in general, the vertical distribution of temperature in different conditions of 

 weather, the influence of humidity, and the bearing of the whole on forecasting. 

 Abstracts of papers on the observations during special phases of weather are also given, 

 .and two tables to facilitate the reduction of the observations. 



30tk June 1902. 



Fig. 7. — an observer at work. 



