MATHEMATICIAN

2pp., 4to. Bifolium. Good, on lightly-aged paper. Black wax seal adhering to reverse of second leaf, which is addressed, with postmarks, by Rigaud to 'Revd. W. T. Hopkins / Elmdon House / Coventry'. He explains, with two diagrams, a geometrical mistake by Hopkins, the letter beginning: 'Your difficulty arises entirely from your imagining that the squares of lines are proportionate to the lines themselves - This is by no means the case'.

1p., 4to. Bifolium. Very good, on lightly-aged paper, with slight traces of mount on reverse of second leaf, which is addressed, with three postmarks and docketing by Spencer, to 'Knight Spencer Esq. | Surry [sic] Institution | Blackfriar's Road'. Gregory is pleased to learn 'that there is a probability of Mr. Jones being able to accommodate us with apparatus for our proposed Lectures, upon such terms as are likely to square pretty well with the funds of the Surry Institution'.

8vo, 1 p. Text clear and complete. On aged and creased paper, with chipping to extremities. Thin strip of stub adhering to reverse, which carries the address in Sanderson's hand: 'Mr: Lowry | No: 57 | Tichfield St:'. He asks him to 'send the Books by the Bearer. | I find my self better & am in hopes of goeing out in a Day or two if weather permits'. He concludes by sending his compliments to Lowry's wife and daughters. Docketed in a contemporary hand at foot of page: 'One of the greatest Mathematicians of this country | Originally (and occasionally till his Death) a Taylor'.

Card (9 x 11 cm), 2 pp. Nine lines of text. Neatly and closely written. Addressed to 'Sehr geehrter Herr Professor!' Placed by Fürth, with a page of his autograph notes, in an envelope addressed by Wrinch 'Herr Doktor Professor Fürth'.

Good firm signature on slip of paper roughly 2.5 x 10 cm. Laid down on slightly larger rectangle of grey paper cut down from leaf of autograph album. A little ruckled, otherwise very good.

Written on both sides of the card, dimensions 5.5 x 9 cm. Good, with a little light scuffing on the front. Communication between two leading lights of French nineteenth-century mathematics. Printed text reads 'VICE-AMIRAL DE JONQUIERES | MEMBRE DE L'INSTITUT | AVENUE BUGEAUD, 2'. Asks Lalanne to 'inscrire Monsieur Bonnaffé, lauréat de l'Institut, parmi les lecteurs'.

12mo, 1 p, 12 lines. Inviting 'M.M. Dupont, père et fils' to help him eat 'le civet d'un lievre qui a eu la Bêtise de se laisser tuer par une femme du hameau du Mousseau'.