26 
Proceedings of the Boyal Society 
as well as of the Academy of Sciences. His diversified abilities as 
an author are well exemplified in the miscellaneous writings col- 
lected by him before his death under the title of Melanges Scienti- 
jiques et Litter air es.^ 
His fame, however, chiefly rests on his scientific productions, 
especially in connection with the polarization of light. His writ- 
ings on astronomy, though voluminous, are not original, except, 
perhaps, in their historical and antiquarian aspect. Even in his 
own subject, that of optics, there did not fall to his share so many 
capital discoveries as from his opportunities, zeal, and unbounded 
perseverance, might perhaps have been expected. His discovery 
(independently of Seebeck) of the rotation of the plane of polariza- 
tion caused by liquids, is the chief of these, and he pursued it 
with unflagging energy into its numerous consequences during at 
least forty years. Biot was an instance of all that mere talent 
and perseverance, unsustained by great genius, can attain. His 
long life was one scene of intellectual labour from first to last. 
Brought up at the feet of the great Laplace, he was perfectly 
conversant with his writings, and with all that belonged to the 
most advanced state of mathematics of the time. His optical re- 
searches were pursued according to the traditions of the same 
school, as contained in the Emission- or Corpuscular-Theory. First 
in his latest years did he begin to betray a consciousness that 
Young, Eresnel, and Arago might be right, and that light is an 
undulation after all. But the imperfect concession had then lost 
all grace. His theory of Moveable Polarization, and generally his 
modes of conceiving complex physical phenomena, were more ela- 
borate than satisfactory. 
One of Biot’s most considerable contributions to science was his 
determination of the length of the seconds-pendulum in different 
latitudes. It was the occasion of (I believe) his only visit to 
Scotland, which took place in the summer of 1817, when he made 
numerous observations at Leith Fort, and then undertook his me- 
morable journey to the Isle of Unst, the northmost of the Shetlands, 
of which he has left an interesting memorial in the first volume 
of his published Essays.f Thus he had the no small distinction 
3 vols. 8vo. Paris, 1858. 
t Taken from the Memoirs of the Academy of Sciences. 
