Vol. 6, 1920 
GEOPHYSICS: C. F. MARVIN 
567 
6. River and Flood Work 
This is one of the most valuable and important activities of the Weather Bureau. 
Service is maintained on all of the navigable rivers of the United States, their tributaries 
and water sheds. Gages are located at suitable intervals on the rivers for determining 
water stages and rain gages distributed throughout the water sheds. Stage readings 
and precipitation are telegraphed daily to district centers where the observations are 
tabulated, summarized and published on the daily weather maps or in bulletin form. 
When conditions warrant, warnings of floods are disseminated to all affected interests 
in the flood areas by telegraph, telephone and other means. 
The saving which results from this service consists in transferring goods, stores and 
other movable property to places of safety. In the south and southwest live stock is 
pastured in river bottoms many of which are subject to overflow in time of flood. A 
notice of the coming of the flood permits the owner of the live stock to drive it out of 
the bottoms, and to safeguard any other movable property that may have been left 
in the threatened region. Forecasts of extreme low river stages are also of much value 
to navigation in many rivers. 
7. Mountain Snowfall and Water Supply Investigations 
This service is maintained in the western states in order to give dependable informa- 
tion relative to the seasonal snow cover, its depth and water content. This informa- 
tion is valuable in determining the probable water supply that will be available both 
for irrigation and power purposes in those states having little or no rainfall in the summer 
months. 
8. Climatological Work 
This work consists of the collecting, compiling, charting, and discussing climatolog- 
ical data of the United States, its adjacent oceans and outlying territories. In addi- 
tion to the observations taken at the more than 200 regular stations of the Weather 
Bureau, observations of temperature, weather, precipitation, etc., are taken by co- 
operative observers located in practically every county of the United States. These 
observations are compiled and printed monthly and disseminated to the public, to 
commercial exchanges, farmers, engineers and home seekers and many other classes. 
The value of this work is incalculable. It affects and benefits the entire people; is 
used in the settling of damage claims, cases at law and for other purposes too numerous 
to mention. In New York City alone the weather records are brought into court by 
personal appearance of a Weather Bureau official more than 500 times a year. Several 
thousand certificates are issued annually over the seal and signature of the Secretary 
of Agriculture for court use. More than 100,000 people annually make inquiry and 
are furnished statements regarding past weather records. The economic value of the 
climatological work of the bureau is enormous. 
9. Agricultural Meteorology 
This service consists in the collection and dissemination of information relative to 
the effect of current weather conditions on farm activities, the growth of vegetation 
and the development of crops and their advancement as compared with an average 
season. Advice is given and information disseminated relative to the utilization of 
the special forecasts and warnings issued by the Weather Bureau in the interest of 
various lines of agriculture and horticulture and stock raising. A number of lines of 
investigations are being conducted as to the relationship between weather conditions 
at various periods of the growing season and crop yields. 
(a) Weekly Weather and Crop Bulletins. — The National Weather and Crop Bulletin 
issued weekly at Washington contains a detailed summary of the weather conditions 
throughout the country for the period covered by each issue and indicates the resulting 
