ADVERTISEMENT 



In connection with the system of meteorological observations established by 

 the Smithsonian Institution about 1850, a series of meteorological tables was 

 compiled by Dr. Arnold Guyot, at the request of Secretary Henry, and the 

 first edition was published in 1852. Though primarily designed for meteoro- 

 logical observers reporting to the Smithsonian Institution, the tables were so 

 widely used by physicists that it seemed desirable to recast the work entirely. 

 It was decided to publish three sets of tables, each representative of the latest 

 knowledge in its field, and independent of one another, but forming a homo- 

 geneous series. The first of the new series, Meteorological Tables, was 

 published in 1893, the second. Geographical Tables, in 1894, and the third, 

 Physical Tables, in 1896. In 1909 and 1922, respectively, two further volumes 

 were added, so that the series now comprises : Smithsonian Meteorological 

 Tables, Smithsonian Geographical Tables, Smithsonian Physical Tables, 

 Smithsonian Mathematical Tables, Smithsonian Mathematical Formulae. 



The 14 years which had elapsed in 1910 since the publication of the first 

 edition of the Physical Tables, prepared by Prof. Thomas Gray, made im- 

 perative a radical revision for the fifth and sixth revised editions published in 

 1910 and 1914. The latter edition was reprinted thrice. The seventh revision 

 was issued in I9i9and was reprinted thrice. The present eighth edition results 

 from a further extensive revision. 



Inconsistencies that will be noted in minor points of style, such as abbrevia- 

 tions, etc., arise from the fact that many of the tables are printed from electro- 

 type plates ; to change them to agree with present usages would involve too 

 great expense. 



Charles G. Abbot, 

 Secretary, Smithsonian Institution. 



March, 1932. 



