1880.] Modern Advances in Meteorology . 239 
to acccount for an abstraction from our atmosphere in some 
years, and an accession to it in others.” 
The fourth leCture, on Clouds and Weather-signs, by the 
Rev. W. Clement Ley, is a most readable and lively chapter, 
and its value is enhanced by a beautifully coloured plate. 
We do not remember any published work which gives with 
such admirable clearness an account of the relation sub- 
sisting between different kinds of cloud and the lines of 
barometric pressure and of cyclonic movement. The 
description in particular of the “ anti-cyclonic stratus ” fre- 
quent during a spell of fine weather in winter, and often 
accompanied by dense ground fogs, is extremely interesting 
and valuable. 
The leCture on Rain, Snow, Hail, and Atmospheric Elec- 
tricity, by Mr. G. J. Symons, is a clear summary of the 
most recent information on these heads, while Mr. R. H. 
Scott, of the Meteorological Office, sums up the whole 
matter with a discourse on the Methods and Objects of 
Meteorology, showing why a scientific knowledge of the 
weather is sought, and what incalculable value it will be to 
mankind. To every profession and calling of mankind, to 
the farmer, the cotton-grower, the sugar-maker, the soldier, 
and the physician, the power of foreseeing and foreknowing 
the conditions of time and climate for a few months or 
weeks ahead would be of priceless moment. The skein to 
be unravelled is truly a tangled one, but thread by thread it 
is being tracked out and unfolded. But three centuries ago 
the advent of comets and the occurrence of unusually high 
tides were regarded as phenomena outside the realm of 
exaCt knowledge, and as defying all calculation. Science, 
which steadily lays hold of the uncorrelated faCts of Nature 
and marshals them into ordered symmetry, has long ago 
conquered the comets and the tides, and has even taken in 
hand the star-showers. Who shall doubt her power also to 
seize upon the laws of wind and weather, tracking them to 
their hidden sources, and making them her own. The 
modern meteorologist is of this faith, and works patiently 
to this end. With Newton he believes that “ the whole 
difficulty of philosophy seems to me to lie in investigating 
the forces of Nature from the phenomena of motion, and in 
demonstrating that from these forces other phenomena will 
ensue.” And with Newton he can add — “ I would that all 
other natural phenomena might similarly be deduced from 
mechanical principles.” 
