470 MR ROBERT COCKBURN MOSSMAN ON 



condensed results of some investigations dealing with various phases of local climate 

 have been included. A table showing the price of wheat in Edinburgh from 1801 to 

 1900 is also given, as the relation of local weather to wheat prices down to about 1872 

 is of an intimate nature. Access to the records of grain prices in the Teind Office was 

 obtained through the courtesy of Mr Nenion Elliot, S.S.C. 



Bright Sunshine, 1890-1900. 



Table XII. shows the total bright sunshine recorded in Edinburgh from August 

 1890 to December 1900. The station was in the Newington district during the whole 

 period, except in the last two months of 1900, when the Eoyal Botanic Garden record 

 was utilised. The sunniest month in this period was July 1897, with 232 hours' bright 

 sunshine, or 44 per cent, of the possible, and the dullest December, 1890, with only 

 seven hours, or 3 per cent, of the possible. The greatest percentage of possible 

 sunshine recorded in any month was for March 1894 — viz. 47 per cent. The annual 

 mean shows 26 per cent, of the possible, the sunniest month being M.a.y, with 34 per 

 cent., and the dullest December, with only 10 per cent. Table XIII. shows the dis- 

 tribution of sunshine through the hours of the day on the mean of ten years. Of the 

 total sunshine registered, 47 per cent, is recorded before noon, and 53 per cent, after 

 noon. Except in May, June and July the sunniest hour is either that ending with 

 noon or 1 p.m. In June the maximum is not reached till between 2 and 3 p.m. In 

 this month and in May the mornings are generally cloudy, with a good deal of fog and 

 haze accompanying the annual maximum of easterly winds. 



In Table XIII. the days are analysed with reference to the percentage of possible 

 sunshine recorded. 



Partial Droughts in Edinburgh, 1857-1900. (Table XIV.) 



In the Transactions (vol. xxxix. p. 146) I gave a list of absolute droughts, which 

 the late Mr Symons defined as periods of more than fourteen days entirely without rain. 

 Partial droughts are much more difficult to define ; in a vague way we know what is meant, 

 but directly any attempt is made to put it into words difficulties arise. Mr Symons has 

 defined a partial drought as a period of " more than twenty-eight consecutive days, the 

 aggregate rainfall of which does not exceed one-hundredth of an inch per day." During 

 the forty-four years ending with 1900, twenty-nine such dry spells were recorded, their 

 mean durations being thirty-seven days. The longest drought was sixty-four days, from 

 April 24 to June 26, 1859. The seasonal variation shows a well marked maximum in 

 June, with 23 per cent, of all the cases recorded. There is a marked fall in May, 

 droughts being then comparatively rare. This may be due to the prevalence of rain- 

 storms caused by the predominating easterly winds. The annual minimum occurs in 



