May 25 52

Moigno

Vous etes bien bon M. et j v^s remercie infin^tM je sincérement d’avoir soutenu mes droits de priorité invention

Plut a Dieu q tous les savans fussent animés d’un pareil esprit de justice Le progrès des sciences en serait merveilleusement avancé Il n y a rien de si décourageant

Quant au microscope polarisant, je ne reclame pas la priorité absolue de l’applicatⁿ de la lumière absolue polarisée aux recherches microsc^ques. Non pas, car Sir D Brewster ^<1> m’a précédé, mais ses charmantes experiences

pour deux ex sur l’applicati (voir planche coloriée ont été faites avec un lentille simple – mais cependant ayant été un des premiers à reconnaitre le grand merite de l’appo l’instrument plaisant qu’on appelle prisme Nicol, ^<2> et le premier à ce que je crois à en donner expliquer l’effet et en donner la veritable [?]

(voir illegible deletion Phil Mag. ^<3>

j’ai été conduit naturellement à en faire applicatⁿ à la microscope composé ce qui m’a parfait^t réussi –

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Translation:

You are very good, Sir, and I am truly thankful to you for upholding my right to the priority of invention.

Please God that all scientists were filled with the same spirit of justice. Scientific progress would be greatly advanced by it. There is nothing so discouraging.

As for the polarizing microscope, I do not claim absolute priority for the application of polarized light to microscopic research. I do not claim it because Sir D Brewster was before me, but his fascinating experiments on apophylite (see the coloured plate made with a simple lens – Nevertheless, having been one of the first to recognise the great merit of the polarizing instrument which is called the Nicol prism, and the first, as far as I know, to explain its effect and to give the true theory,

(see Phil Mag.

I was naturally led to apply it to the compound microscope which worked perfectly –

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Notes:

1. Sir David Brewster (1781–1868), Scottish scientist & journalist.

2. Invented by William Nicol (1768–1851), in 1828, this prism consisted of a piece of Calcite, or Iceland Spar, cut diagonally and cemented back together.

3. ‘Facts relating to Optical Science, No. II: On Mr Nicol’s Polarizing Eye-piece’, Philosophical Magazine, v. 4 no. 2, April 1834, pp. 289–290.