134 KANSAS CITY REVIEW OF SCIENCE. 
the latter. He does not deny the existence of an ice-sheet, but ridicules the idea 
of a confluent ice-mass moving in different directions, and attaches great import- 
ance to the work of icebergs and rivers. He ignores the erosive powers claimed 
for glaciers and refers the multitudinous rock-basins of Canada and Finland to 
chemical decomposition and orographic displacement, asserting that the tendency 
of streams is to deepen these basins, rather than obliterate them. A wider dis- 
cussion of these views is promised in a succeeding volume. 
In microscopic science the principal event has been the result of experiments 
by Dr. Koch, of Germany, in the investigation of Pasteur's discoveries in the* 
germ theory of disease. It is the bacterial or parasitic origin of tubercular 
disease, and consequently of its infectiousness. These discoveries of Dr. Koch 
were from a multitude of observations in which he demonstrated the invariable 
presence in tubercular material of myriads of minute organisms, possessing all the 
characteristics of bacilli, with which he succeeded in inoculating Guinea pigs,, 
rabbits, cats, and other animals with the disease. Not only was this done with 
tuberculous matter taken directly from diseased animals, but with bacilli which 
had been taken from cultivation and reproduction in a pabulum extending over a 
period of six months. These researches are so well fortified that they appear to 
have met with almost universal acceptance. 
The recent storms throughout the country, and the protracted dry season pre- 
ceding, may make the following fact of interest at this time. While not a dis- 
covery to scientific men, yet it has not been generally known that the spectro- 
scope can be used as a weather indicator, by the intensity of the so-called rain- 
band — the absorption spectrum of aqueous vapor — which occupies a portion of 
the solar spectrum. Its indications are said to be infallible in predicting the state 
of the weather for a day or even two days in advance. Spectroscopes for this 
purpose have been made by opticians, so small that they can be carried in the 
pocket, and so sensitive and true that a glance through them is sufficient for the 
experienced observer to forecast the condition of the atmosphere and determine 
with certainty the coming weather. The principle is this : There is more or 
less vapor always in the air, and the density of this vapor, more or less, deter- 
mines what we call wet or dry weather, and the spectroscope shows the condition 
immediately by its power of discriminating the differently colored rays of which 
white light is made up. The molecules of water have the power of shutting out 
certain of those rays and placing them in the order of rainbow colors by the prism 
and slit of the spectroscope, but transmitting others freely. In looking through 
a properly adjusted spectroscope at the sky, we see besides the regular series of 
colors from red to violet, and besides all the thin dark Fraunhofer or solar lines, 
in one place, that between the orange and yellow of the spectrum, a dark hazy 
band stretches across it. This is the band of watery vapor. The look should 
be to the clear sky where it is fullest of light, at a low rather than a high angle of 
altitude. Any extreme darkness of this band beyond what is usual in the locahty 
of the observer and the season of the year is a sure indication of the abnormal 
presence and accumulation of rain material, and on the contrary any deficiency 
