80 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



ing to fully consider the conclusions which he thus sums 

 up : "From this investigation it results that if in the deter- 

 mination of annual mean temperature and its periodic varia- 

 tions the influence of the local peculiarities of the place of ob- 

 servation can not be recognized, then in the determination of 

 the non-periodic variations of temperature in the neighboring 

 stations its influence will be so unimportant that it can be 

 neglected, presuming throughout that there is no important 

 difterence of altitude in the stations. 



" In my investigations into non-periodic variations, I have 

 always referred the deviations of individual years to secular 

 mean values derived from a very long series of years, which 

 secular means were determined for the same years for the 

 stations under examination. Since for but too few stations 

 there exist these long series of observations, it was necessary 

 to find a method of deriving secular means for the stations em- 

 bracing a few years of observation, such as would have been 

 given by a long and simultaneous series. I have, therefore, 

 for the neighboring so-called normal stations, for which I had 

 a long series of observations, computed the means resulting 

 from the use of only the same years as those for w^hich ob- 

 servations at a short-period station were available. The dif- 

 ference between this mean and the secular mean gave a cor- 

 rection to be applied to the mean for the secondary station, in 

 order to obtain for it a number corresponding very nearly to 

 what would have been its secular mean." This process im- 

 plies the assumption that the non-periodic variations of the 

 two neighboring stations were identical. The present inves- 

 tio-ation contains a strikino: confirmation of the correctness 

 of this method of procedure, now so generally applied. 



A communication has been made to the Academy dei Lin- 

 cei, of Rome, by M. Tarry, giving the results of his personal 

 experience and investigations into the connection between 

 the cyclonic storms and the showers of sand that frequently 

 visit Southern Europe. 



M. Tarry, after traveling as secretary to the French Mete- 

 orological Society into Northern Africa and the Desert of 

 Sahara, and having consulted the files of the Daily Weather 

 Bulletin of the Paris Observatory, believes himself to have 

 established the fixct that Avhenever a cyclone passes south- 

 ward from Europe over the Mediterranean Sea into Africa 



