586 



Calculated for C.H^SO, : 132. 



Hence, the crystallized compound is formed from one mol. of 

 isoprene and one mol. of SO.. 



The substance is soluble in water. The aqueous solution has a 

 neutral reaction. 



If a solution of the compound in carbon tetrachloride or ether is 

 shaken with a solution of bromine in the same solvent, the colour 

 of the bromine is not discharged ; bromine water, however, is 

 gradually decolourised. With dilute alkaline potassium permanganate 

 a reduction sets in at once. 



As to the structure of this compound I do not as yet venture 



to pronounce an opinion. In connexion with Thielk's theory the 



occurrence of a compound of tiie formula CHj — C[CH3] = CH — CHj 



I SO, I 



would not be improbable. 



Utrecht. Org. Chem. Lah. University. 



Geophysics. — ''The treatment of frequencies of directed quantities''. 

 By Dr. J. P. van der Stok. 



(Communicated in tlie meeting of June 27, 1914). 



1. The frequency-curves of barometric heights, atmospheric 

 temperatures and other meteorological quantities assume different and 

 peculiar forms, which can be considered as climatological charac- 

 teristics and, as the number of available data increases, it is desirable 

 to subject these curves to such a treatment that these characteristic 

 peculiarities are represented by climatological constants. 



Tf we choose for this purpose the development in series-form, the 

 first question is, what treatment is to be chosen for each special 

 case, in conformity with the distinctive featni-es of the quantities 

 under consideration and the limits between which they are com- 

 prised. The purpose of this investigation is to inquire, what form 

 is to be chosen for frequencies of wind-velocities independent of 

 direction, and of direction without regard to velocity. Furthermore, 

 to state in how far the observed series of quantities may be regarded 

 as normal- or standard-values, and the problem may be stated also 

 in this way : what is the best form for frequencies of directed 

 quantities assuming the form of linear quantities, and further, how 

 to integrate the expression 



