S08 M. Van Svvinden on the Invention of Pendulwn-Clocks 
iiendi ratione^ et accurata horologiorum ratione in which he 
thus expresses himself : M. Huygens of Zuilichem, a Hol- 
lander, claims the invention and practical application of pen- 
dulum-clocks, in his treatise dedicated to the States of Holland, 
from which he afterwards obtained an exclusive privilege, as 
likewise from the King of France.:’ (This is inaccurate ; the 
privilege was of the States- General, and granted the year h^ore 
the publication ; nor did he obtain the privilege from the King 
of France, though he applied for it). “ But Count Magalotti, 
Resident on the part of the Grand Duke of Tuscany at the Im- 
perial Court, contradicts him, who told .me in person the whole 
history of that clock ; the same was told me three years ago 
in the same manner at Augsburg by Trefler, watchmaker of 
the late Grand Duke*]*, father of the present. Namely he 
relates having, by order of the Grand Duke, and in the spirit 
(instlnctu) of his mathematician Galileo Galilei, made the first 
pendulum-clock ( Horologium Pendulum ) at Florence, of which 
a specimen was sent to Holland. The mathematician of the 
late Elector of Mentz, told me he had seen at Prague a pendu- 
lum-clock, made by J ustus Borgen, mathematician and watch- 
maker to the Emperor Rudolph II., of which the great mathema- 
tician, Tycho Brahe, had made use in nis astronomical observa- 
tions.” This statement of Becker has found its way into several 
works, and has been admitted, without farther inquiry, by some as 
containing facts uncontroverted by any species of evidence, except 
the known integrity of Huygens, by others as undoubted truth, 
and farther commented upon in an eulogy on Galileo, originally 
published at Milan, in an Italian Journal del Cqffe^ afterwards 
in the third volume of Ehgi degli Uomini illustri di Toscana, 
printed at Lucca in 177^. The writer of this last work, in men- 
* Reprint^ in the Physica Subtermnea. The judgment of Flamstead and 
Hook upon it was any thing but favourable. See Birch’s Hist, of the Royal Soc. 
iv. 17. Leibnitz drew a still worse picture of the man, Op. vi. 333. His language 
about Huygens appears certainly not very creditable, after he had, in 1 660, on a 
visit to Holland, requested the honour of his acquaintance, to shew him a per- 
pietnum mobile, with some little flattery to a man, “ Quern in Mechanicis ob Ho- 
rologium a te (Huygenio) inventum celebrari intellexit.” {Leyden MSS.) 
*}* Ferdinand H. dead in 1670 ; he was brother of Leopold de Medicis, before 
mej^tionedo 
