48 REPORT OF THE SECRETARY. 



pecuniary compensation is made to observers, the facilities exten ed 

 to them, besides the reports and other documents occasionally dis- 

 tributed, though not expected to be a remuneration for the time and 

 labor devoted to the subject, are still of some value. An inducement 

 also exists in the pleasure to be derived from the study of the changes 

 of the phenomena of nature, besides the consciousness of co-operating 

 with many others in a system intended to advance an important branch 

 of science. 



Although the information derived from the system of observations? 

 under the immediate direction of the Institution, is exceedingly'* 

 valuable in many points, it is to be regretted that changes in the 

 observers are so frequent. The value in determining the great ques- 

 tion as to the periodicity of the weather and its average conditions 

 as to heat, moisture, cloudiness, occurrence of frosts, &c, other things 

 being the same, depend upon the length of time the series of observa- 

 tions have been continued, and results which may be relied upon 

 as the element of insurance against failure of crops and disasters by 

 storms are valuable strictly in proportion to the number of years 

 embraced in the observations. 



The reason why meteorology is not further advanced is not on 

 account of the want of observations, but of extended series at a 

 number of properly chosen places. From observations of this kind 

 it is found that much of the apparent irregularity and caprice of the 

 weather is due to our limited vision, and that by extending the records 

 and properly studying them, many phenomena which are apparently 

 fitful and exempt from all law will be reduced to order and periodicity. 



According to Mr. Glaisher's investigations of the records made at 

 the Royal Observatory for a long series of years, there is a rotation 

 in the character of the weather at London about every fifteen years, 

 the seasons growing warmer and warmer until they reach a maximum 

 of temperature, and then gradually colder until they come to the 

 lowest point, when they begin a new cycle of temperature. A series 

 of meteorological tables may appear to the casual observer a mere 

 mass of dull, uninteresting figures, yet a little study will enable us, 

 says a popular writer of the day, to read in them the past history of 

 "rich harvests, prosperous commerce, good health, plenty, and con- 

 tentment; or, perhaps, the gloomier side of the picture, scanty crops 

 and high prices, stagnant trade and social irritation, prevalent diseases 

 and busy death;" and, it might be added, a still greater interest is 



