Nécrologie : Henri PERRIN

Jean Perrin

1. The first indication of the phenomenon.-When we consider a fluid mass in equilibrium, for example, some water in a glass, all the parts of the mass appear completely motionless to us. If we put into it an object of greater density it falls and, if it is spherical, it falls exactly vertically. The fall, it is true, is the slower the smaller the object; but, so long as it is visible, it falls ...

Charles-Jules-Henri Nicolle

sia. Nicolle's many accomplishments include the discovery that epidemic typhus is transmitted by body lice (Pediculus humanis corporis), discovery of the phenomenon of inap-parent infection, and possibly the first isolation of human influenza virus after experimental transmission. Nicolle made many other fundamental contributions to knowledge of infectious diseases. This year is the centenary o...

Henri De Mondeville *

Henri ’ s Crystal Ball

O n April 10, 1908, at the general session of the Fourth International Congress of Mathematicians held in Rome, Gaston Darboux presented a talk by Henri Poincaré (1854–1912) entitled The Future of Mathematics (Poincaré was unfortunately unable to deliver the talk himself). The original can be found on the web at: http://gallica. bnf.fr/ark:/12148/bpt6k17083c/f934n10. capture. It is now a full c...

Preface Henri Darmon

Modular curves and their close relatives, Shimura curves attached to multiplicative subgroups of quaternion algebras, are equipped with a distinguished collection of points defined over class fields of imaginary quadratic fields and arising from the theory of complex multiplication: the so-called Heegner points. It is customary to use the same term to describe the images of degree zero divisors...