6 FEBRUARY 1926, Page 21

Atomicity and Quanta (Cambridge University Press, 2s. 6d.), by Professor

Jeaas, should be mentioned as being a pronounce- ment by one of the most eminent of mathematicians. It is not for the vulgar, however, but for those who can solve wave- equations in electro-dynamics and explore those regions of Higher Mathematics where electrons and radiant energy are considered. * * * *