Faraday to Achille Brachet   31 January 1857¹

Royal Institution | London | 31 January 1857

Sir

I write in haste as you desire in reply to your enquiry - I do not think that there is any manufactory of such heavy flint glass as that I made many years ago² nor do I think that such glass can be obtained commercially[.] That which I had has been gradually dispersed amongst philosophers because of its value in investigations regarding the action of magnetism on light[.] I am very sorry to have so barren an answer to give to your enquiry[.]

I have the honor to be | Sir | Your Very humble Servant | M. Faraday

Monsieur | M. Achille Brachet | &c &c &c