328 Letter to Mr. Arthur Aikin 



infirmity of his viemory, and the hnJdiual confas'ion of his 

 ideas, he mistook the appearance for therealiti/, and has ever 

 since believed that Venus has a moon, instead of being in 

 some respects like one." 



Without dwelling on the observations which you make 

 on my work in general, I shall confine myself to the present 

 point, as you accuse me of having published a direct false- 

 hood. 



Had my work been professedly on astronomy, I should 

 have given my authorities; but as the fact denied in your 

 Review was onlv added as a note, and incidentally men- 

 tioned, I thought myself excused till called upon to vindi- 

 cate my own veracity from such animadversions. My astro- 

 nomical observations were extracted from Bonnet's Contem- 

 plation de la Nature, vol. iv. part 1. This author says 

 (page 7), " Venus and the earth have each a satellite," and 

 adds in a note the following proofs in support of what he 

 advances * : 



" A great manv doubts have been started in regard to the 

 existence of the satellite of Venus, and it has been suspected 

 that the accounts given of it by different observers arose 

 chiefly from some optical illusion. But those who take the 

 trouble to consult the article Venus in the Supplement to 

 the French Ency doped' e, vol. xvii, will entertain no doubt 

 of the existence of this planet. They will find there an ob- 



Arc these gentlemen botanical painters ? No. Tliey must then have 

 been done under his eye and direction, and Dr. Thornton in this way 

 participates in tlieir fciine.— EuiT. 



'■' On a elevc bicn dcs doutcs sur I'existence du i^attUire de Venus; 

 on a soupqotine que ce qui en avoit etc rappone par ditfcrens observateurs, 

 tenoit principalement a queiqu'illusion d'optique. Mais, si Ton prcnd la 

 peine de consultcr Tarticle Venus du Supplement a. I' Encyclcpectk de 

 Pans, torn, xvii, on ne doutera gueres de I'existence du satellite dont il 

 s'agit. On y veira lohservation du grand Cassini de i686,celles de Mr. 

 Sho^ t de 1740, de Mr. Montait^ne de 1761, du P. la Grange de la mCnie 

 annet, de Mr. Monlbaion de 1765. C'avoir etc sous la forme d'un petit 

 croissant que le satellite s'etoit inonticsux trois premiers obseivateurs que 

 je viens de citer. Mr. Short ?.voit ete si louche de sa propre decouverte, 

 qu'il I'avoit fa.t graver sur son cachet avtc cctte devise, lande.m al>parui!. 

 Le celtbre Lambert, qui a compare entr'elles toures les observations de ce 

 satellite, a montre leur accord. Essni il'uneT'hcorif du Saullitede Venus, 

 No-i'Vf.aux Mem'jircs di: i Academic- dr- Berlin, an. 1773. Suivsnt lis cal- 

 culs de cet astronomc, la revolution de ce satellite autour de Venus se- 

 roit a-pcL'-pres de onze jours. 11 avoit cru qu'on pourroit I'apjn rcevoir 

 sur le disque du toleil, Ic I de Juin 1777, parce que Venus devoii passer 

 alors tres pres de cet astre; mais on ne I'v a pas decouvert. M. de- 

 Mairan, qui ne paroissoit pas dourer de I'existence de ce petit astre, avoir 

 indiqus les causes de la rarete de scs apparitions. Men. de I'Aead. de 

 Palis, 1762. * 



,1 servatlon 



