The transcript of this letter is:
May 9 1896
Dear Sir
I have considered the question of purchasing your collection of Playing Cards and have decided not to do so. I may however hear of someone who would like such a collection, and if I do I will put the matter before him.
Yours very truly
J.N. Maskelyne
H. Evanion Esqr.
It would appear that this letter was once in the Jimmy Findlay Collection. Jim Hagy mentions in his book on Evanion that: ‘Findlay possessed in his collection a letter from Maskelyne to Evanion dated May 9, 1896 declining to purchase the latter’s playing card collection’. (Early English Conjuring Collectors: James Savren and Henry Evanion by James Hagy, Second Edition published in 2020 by Reginald Scot Books, Glenview, USA, page 72.) Jim’s excellent book is the place to go to for information on Evanion.