NoTES ON TREES. 41 
these records gave no evidence of either a deterioration or an 
improvement in the climate, though there appeared to be fairly 
well-marked oscillations. Again, in Russia we have a country 
where internal trade depends largely on its navigable rivers, 
which are frozen during the winter months. The dates of the 
opening and closing of the rivers to navigation are known with 
tolerable certainty for the last two hundred years, and it 
appeared as though exceptionally cold years occurred at 
intervals of from thirty to thirty-five years and exceptionally 
warm years with a similar period. Probably in our islands also 
there were such oscillations, but accurate instrumental obser- 
vations were an affair of the last half-century, and that was 
too short a time on which to base an opinion. 
In the course of his remarks, Mr Watt pointed out that 
exact statements as to our climate were made possible only by 
the painstaking work of observers in various parts of the country. 
In the south of Scotland the Cargen observations and those by 
Mr Andson in Dumfries were of great value. 
The lecture was freely illustrated, many of the lantern slides 
being from original diagrams. Of special local interest was a 
slide showing the annual rainfall at Cargen for the last forty 
years. 
ith December, 1906. 
Chairman—The PRESIDENT. 
Notes ON TREES. By Mr W. J. MAXWELL. 
The following are some notes on various kinds of trees now 
available for planting, which I hope may not be without interest. 
A few days ago I measured some trees growing at Terregles. I 
find that a Douglas Fir, one of several of the same age and size 
which was planted in 1886, has reached the height of 53 feet, 
with a girth, at about 4 feet from the ground, of 44 feet. Picea 
nobilis, planted in 1885, have attained about the same dimen- 
sions. A Thuya gigantea, supposed to have been planted about 
1882, but perhaps really five or, six years earlier, is 61 feet high 
and 6 feet 10 inches in girth, with very wide-spreading branches 
