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meteorology to anything like an exact science. We can tell what has been, 
but I question very much whether we can tell what is to be. 
Mr. Baldwin Latham, M. Inst. C.E. — It makes no difference whether we 
collect rain from the roofs of our houses or from a large area of the earth’s 
surface, called by engineers a “gathering-ground,” or if we obtain water from 
springs, or take it from wells sunk into the earth ; all these sources of water 
supply are entirely dependent, and are solely due to rainfall. The science 
of meteorology at the present day is making rapid progress, but there is little 
doubt that some centuries ago much more was known with regard to the 
laws of the atmosphere than is known at the present day. Hippocrates 
taught his disciples that they could foretell the state of the seasons, and, as 
a consequence, what diseases would afflict mankind at particular periods. 
This, he said, was due in a measure to the observations made of the motions 
of certain stars. What was the nature of these observations we do not now 
know ; but Professor Balfour Stewart appears, from his investigation, to 
think that even the stars have some influence on the atmosphere, as they 
have some influence on the sun spots. Before the advent of Hippocrates, 
the influence of stars on the atmosphere seems to have been known. In 
the sacred books of the Parsees, the Khordah Avesta, the influence of a 
star is set forth as causing the presence or absence of rain, and the absence 
of rain is clearly shown as a condition of things which produces disease. In 
our own country the climate is, to a certain extent, uncertain, because of the 
smallness of the country, whereby the general laws in operation are every- 
where modified and interfered with by our being surrounded by so much 
water ; we also occupy a position in which a constant interchange takes 
place between currents of air moving from the direction of the tropics and 
the arctic regions, which cause great alternation in the climate, but 
the nearer to the equator and the sun’s path we go, meteorological condi- 
tions are always much more defined and certain, and you can there predict 
with certainty, for many months beforehand, what the weather is likely to be. 
Eainfall is entirely due to the heat of the sun and the diurnal motion of the earth. 
The air travels with the motion of the earth, from west to east, and that is 
the reason why the storms travel in that particular direction, and why our 
western coasts receive the largest amount of rain. But rain falls on the sea 
as well as on land. Very heavy rains take place at sea, and the reason for it 
is that, if the rains were always following in defined lines, we should have tracts 
of country in which there would be a large amount of rainfall, and tracts in 
which there would be practically dryness. But the wind is not moving in 
straight lines, but gyrates in circles. When the wind gyrates in a circle in 
which the movement is in the opposite direction to the hands of a watch, we 
call it a cyclone ; and when this movement takes place, the air is moving 
upwards from the surface of the earth. When the wind gyrates in the same 
direction as the hands of the watch, we call the period anti- cyclonic, and at 
such times the air is moving down from the higher regions towards the 
earth’s surface. In a cyclonic movement, the air is moving from a warmer to 
a cold region, and this movement is usually attended with rain, for as the air 
