REVIEWS. 
411 
we are dealing with reports from an extensive tract of country, as North 
America, or the continent of Europe, the distribution of the moisture or of 
the vapour-tension will afford great assistance in tracing out the probable 
motion of storms.” He here shows us, what many are not aware of, the 
great importance of the wet-bulb thermometer, for it is by means of this 
instrument that the amount of moisture in the atmosphere is ascertained. 
And further on he points out the important fact that most of our meteoro- 
logical stations are situated at the sea-side, where the atmosphere is 
almost always laden with moisture. They are, therefore, by no means so 
valuable for the determination of advancing rain as the more inland 
observatories. 
In regard to the barometer, or rather the weather-glass, taken by itself 
as a guide to the state of the weather, Mr. Scott points out that this 
method is utterly absurd. We must quote him again on this point : — “ Let 
us take, for example, the word ‘ Change.’ This is placed opposite the 
reading 1 29 o inches,’ which reading is naturally supposed to be taken at 
sea-level. If the barometer be removed to a station situated say 500 feet 
above that level, the corresponding reading will be about 29'0 inches, so that 
the whole scale will be half an inch out, and the error will be greater the 
more considerable the height of the station. The lettering is, therefore, 
again wrong, because it does not take account of the necessary reduction of 
the reading to sea-level. Once more, the range of the barometer is far 
greater in winter than in summer, so that the reading which corresponds 
to ‘Fair’ should be much nearer to 1 Change ’ in summer than in winter 
. . . The words are , in fact , little less than utter nonsense .” 
The subject of gradients is very fully gone into by Mr. Scott, and the reader 
will follow his remarks with considerable interest. The chapter on cyclones 
and anti-cyclones shows us clearly how much work remains to be done to 
satisfactorily clear up our knowledge on the subjects. Indeed, on this 
question, which is complex enough, we do not see that very many con- 
clusions can be drawn. However, such as they are, the author gives them 
to us. Another problem, that is certain to be more clearly ascertained as 
researches go on, is that of the motion of storms and the agencies affecting 
it. On this, too, Mr. Scott has told us all that is known. Of much 
interest are the author’s observations on the connection (for there is an 
undoubted connection) between sun-spots and cyclones. He says, “ Of late 
years Mr. Meldrum, of the Mauritius, has shown that the cyclones, for 
which that district of the Indian Ocean enjoys an unenviable notoriety, 
have been more frequent in some years than in others, and that these epochs 
of maximum frequency occur at intervals of about eleven years, coinciding 
with those of maximum sun-spot frequency.” He then asks the question, 
why it has been left to Mr. Meldrum to arrive at this discovery P and he 
gives two excellent reasons why it should have been so. 
Then he points out the nature of the well-known storm-signals — which 
were frequent enough in Admiral Fitzroy’s time — and he shows us what we 
certainly are surprised to learn, that there has been great success in the 
prophetic department of the Meteorological Office in regard to its signals to 
Hamburgh. He says, “ A system of warnings for Hamburgh, from our 
office, has been in operation since 1867, and the general results are that 
