INTRODUCTION. 



The meteorological observations reduced and discussed in the following pages 

 were made between the years 1817 and 1859, inclusive, g.t Marietta, the oldest 

 town in the State of Ohio. It is situated at the junction of the Muskingum and 

 Ohio rivers, in latitude 39° 2^' and longitude 81° 29' W. of Greenwich; and is 

 elevated about 580 feet above the ocean. 



The Hon. Josiah Meigs, Surveyor-General of the United States, directed that a 

 journal of the weather should be kept at the Land Office in Marietta, including a 

 record of the temperature, fall of rain, and the state of the sky. The records of 

 the earlier observations of this series are not now to be found, but those made 

 by Mr. Wood, between 1817 and 1823, inclusive, and the continuation of them 

 until 1859, by the late Dr. S. P. Hildreth, were presented to this Institution for 

 analysis and publication. A small portion of the manuscript was lost in the fire 

 which destroyed a part of the Smithsonian building in 1865. Fortunately the 

 deficiency thus caused was supplied by the publication of the monthly means in 

 SiUiman's Journal of Science and Arts, Vols. XVI to XXVII, 



The records were given in charge to Mr. Schott, and have been discussed on 

 the general plan adopted for other observations previously published by the In- 

 stitution. 



The Institution is indebted to Dr. Geo. O. Hildreth for information as to the 

 instruments used by his father, and other facts relative to this valuable series of 

 observations. 



JOSEPH HENRY, 



Secretary, S. I. 



Smithsonian Institution/ 

 May 20, 1868. 



( ill ) 



