HENRY SOTHERAN & CO., 140, STRAND, W.C, AND 43, PICCADILLY, W. 531) 



10672 LEECH (Thomas, f.c.s.) Dozens versus Texs, or the Ounce, the Inch, and the Penny, 

 considered as Standards of Weight, Measure, and Monej^ and with Reference to a Duodecimal 

 Notation, cr. 8vo. cL, 2s 6d 186& 



10673 LEEDS (Frank Henley, f.i.c ), and William John Atkinson BUTTERFIELD: 

 Acetylene : a practical Handbook on the Principles of its Generation and Use ; 2tid [latest] 

 Edition, enlarged, with 62 illustrations and 2 folding tables, large cr. 8vo. c/., 5* 6rf (p. 8s Qd nett) 191(> 



10674 LEEDS (Lewis W.) Treatise on Ventilation : showing the great VVant of Improved 

 Methods of Ventilation in our Buildings, 2nd Edition, with 12 coloured plates, and numerous 

 woodcuts, Svo. hf. calf, or, hf morocco (title stamped), 4s New York, 1876 



LEEKE (John)— V. Caus (iVo. 729), and Foster (N'o. 8051-2), ante. 



10675 LE FEBTJKE (Nicasius, recte Nicolas, prof, chemistry to Charles II.) A Compleat Body of 

 Chymistry : wherein is contained whatsoever is necessary for the attaining to the curious- 

 Knowledge of this Art ; comprehending in general the whole Practice thereof ; and teaching the 

 most exact Preparation of Animals, Vegetables and Minerals, so as to pre^^erve their essential 

 Vertues, rendred into English by P. D. C, Esq. one of the Gentlemen of H.M.'s Privy Chamber; 

 wn7A ^folding copperplates, 2 parts in 1 vol. sm. 4to. old calf, rebacked {first title and last 2 II. 

 soiled, and the former mounted) ; RARE, £1. 5s Tho. Ratcliff^, 1664 



FiBST Enui.isu Edition of this early treatise on theoretical chemistry. ' Premier ouvrage de ce genre. Un sentait 

 dcpuis longtemps le besoin Ue reuiiir en un corps de doctrine les matdriaux disperses un peu partout. Le ' Traite de 

 Chimie ' de Leievre repondait ;i ce besoin de I'epoque ; et c'est ce qui en explique le sucres.' — F. Hocfer. 



10676 LEFilBUBE de FOURCY (Louis Etienne) Elements de Trisonometrie, 7® Edition ; with 

 folding plate, Svo. sewn. Is 6rf , Mons. 185;i 



10677 Lecons d'ALGiiBRE, 6° Edition, Svo. cl., with auto, of Richard Congreve, PositiviU 



(1818-1899), 2ir,rf ISoO- 



10678 Lecons Je Geometrie Analytique, coraprenant la Trigonometrie Kectiligne et 



Sph6rique, etc., 5*^ Edition ; with \\ folding plates, Svo. hf. morocco neat, 3s 1846- 



10679 Neuvieme Edition ; with \\ folding plates, Svo. cl., 3s 6rf 1871 



LEFilVRE d'i:taples (Jacques)— v. Faber Stapulensis, no. 7736 ante. 



106cS0 LEGENDBE (Adrian Marie; F.R.S.) Elements de Geometrie, avec des Notes ; premiere- 

 edition ; with 1 1 folding plates, Svo. old calf (rubbed), 5s 17 94 



10681 Elements of Geometry and Trigonometry, with Notes, translated from the French ; 



edited by Sir David Brewster, f.r.s., with Notes and Additions, and Introductory Chapter 

 on Proportion [by Thomas Carlyle], diagrams, Svo. cl. (scarce), ivith auto. ofT. R. Birk.%. pr. 

 (1810-83), 125 6<^ Edin.,lH24r 



Of special interest for the essay by the historian— his only contribution to the exact sciences. The tran.slafion was 

 also by Carlyle, who was recommended to undertake the work by Sir David Brewster, f.r.s., and receivel for it £50. 



10682 Theorie des Nombres, 3^ [la meilleure] edition [avec Appendice : Methodes 



nouvelles pour la Resolution Approchee des Equations Numeriqiies, etc. etc.] ; loith folding plate, 

 2 vols. 4to. hf. calf (VERY rare), £2. 15* Didof, 1830 



The BE-ST EDITION, NOW KXCE.SSIVELY SCARCE. 'The third edition, issued in 1830, includes the results of his variou* 

 later papers, and still remains a standard woik on the subject. It may be .«aid that he here carried the subject as far 

 as was possible by the application of ordinary algebra. . . . The law of quadratic reciprocity, which connects any two odd 

 primes, was first proved in this book. Gauss called the proposition 'the gem of arithmetic, . . . This work also contains 

 the useful theorem by which, when it is possible, an indeterminate equation of the 2nd degree can be reduced to the form 

 nx'2 + bi/i + cz-i = O.'—JV. W. R. Ball. 



1CG83 : Davies (Charles) Elements of Geometry and Trigonometry from the Works of 



A. M. Legendre, adapted to the Course of Mathematical Instruction in the United States, 

 ivith numerous diagrams, Svo. calf (binding vjorn), 2s 6d New York, 1876 



10684 LEGGATT (William) The Theory and Practice of Jute Spinning : a Complete Description 

 of the Machines used in the Preparation and Spinning; of Jute Yarns ; with 4 plates (2 J aiding), 

 ami about 140 other illustrations, cr. 4to. d., Qs (p. 10* &d nett) Dundee, 1893 



10685 LEGOYT (Alfred) Le Livre des Chemins de Fer Construits, en Construction et Projetes, on 

 Statistic^ue G^n^RALE de ces Voies de Communication en France et a I'Etranger, post Svo. sewn 

 (scarce). Is 6d 1845 



Including the United States. Several English names are mo.st delightfolly traiiSmogrified, sc. that early venture, never 

 yet used for passenger traffic, the Thames Haven line appears anthropomorphically as Thomas Havendock, and the line 

 which maile Cardiff as the Toffvale. 



10686 LE GBAY (Gustave, peintre et photographiste) Fhotografhie : Traite Nouveau, theorique 

 et {)rati(iue, des Proced^s et Manipulations sur Papier Sec et Humide, et sur Verre au 

 Collodion et a I'Albumine, premiere edition^ roy. Svo. sewn (scarce), £1. Is 



Lerebours et Secretan [1852] 

 This work, besides being a risume of all then known of photography, gives several new processes ; but is of still greater 

 interest in connexion with the rival claims of the author and Frkderick Scott Archer (1813-57) to the discovery of the 

 COLLODION PR0CE8.S. The latter (according to J). N. B.) ' in 1S50 successfully applied collodion to photography. . . . The 

 first account was published in the ' Chemist ' March 18.51.' Le Gray however in the preface to the above work states that 

 he had already made the discovery in 1849, but attached little importance to it, and recommends it only ' sous le rai)port 

 de la finesse et de la rapidite.' Pp. 89-1 11 give a description of his collodion process. The announcement of the discovery 

 appeared in the English translation of 1S.50 (q. v. infra). 



10687 Practical Treatise on Photography, on Paper and Glass, translated by Thomas 



Cousins, post Svo. (pp. 24), seivn (scarce), 10* 6rf 1850 



In the appendix the author announces his invention of the collo<lion process, which however had already been 

 discovered and used by Frederick Scott Archer, who unfortunately for himself never thought of taking out a patent, and 

 after a few years died a poor man. 



'I have just discovered a process upon glass, by hydrofluoric ether, the fluoride of potassium and soda dissolved in 

 alcohol 40% mixed with sulphuric ether, and afterwards saturated with collodion ', etc. etc. etc.— i'. 24. 



10688 Photographic Manipulation : the Waxed Paper Process, translated, 12mo. 



(pp. 23), sewn (scarce), 5s 1853 



