98 THE EFFECTS OF FORESTS ON MOISTURE 



"AqcI it is remarkable in this table that for the years 1851- 

 1850, two different observers obtained quantities of water notably 

 differe nt." 



The work of M. Raulin presents other examples of such anomalies. 

 To these I shall afterwards have occasion to refer in the further pro- 

 secution of the study of the subject ; but from the recorded observa- 

 tions, the destruction of forests in the districts I named does not 

 appear to have greatly affected the deposit of moisture throughout 

 the districts referred to. 



Corresponding results have been yielded by a study of the records 

 of observations made in the United States of America. 



In North America we have a country which within comparatively 

 recent times was extensively covered with forests in regions which 

 have now been in a great measure cleared of them. To observations 

 which may indicate any changes upon the rainfall over extensive 

 districts which may thus have been produced attention has been 

 given, and is being given, by fhe Smithsonian Institution, under the 

 direction of the Secretary, Professor Joseph Henry, at Washington. 

 Under his direction there are being collected, collated, tabulated, and 

 otherwise utilised, meteorological observations made throughout the 

 United States, observations made at sea, and collected at the United 

 States Naval Observatory, observations made by Arctic and Ant- 

 artic explorers, and observations made at several hundred stations in 

 other parts of the world. 



Observations on the winds of North America have been tabulated 

 and published, and have been largely made use of by the English 

 Board of Trade in constructing wind charts of the Northern Ocean. 

 In 1872 Professor Coffin was engaged in the tabulation of observa- 

 tions in parallel zones of latitude 5^^ in breadth, the whole world over, 

 from the North Pole to the South. And at that time it was reported 

 by Professor Henry : — 



" The temperature observations ai*e still in progress of reduction, 

 two computers being engaged upon the work. The progress of their 

 labours has, however, frequently been interrupted by calls from 

 different portions of the country for reports on the climate of 

 different districts. 



" The following is an account of the present condition of this part 

 of the general reductions : 



" The collection and tabulation, in the form of monthly and 

 annual means, of all accessible observations of the atmospheric tern- 



