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



10672 LEECH (Thomas, F.C.S.) DOZENS versus TENS, or the Ounce, the Inch, and the Penny, 

 considered as Standards of Weight, Measure, and Money, and with Reference to a DUODECIMAL 

 NOTATION, cr. 8vo. cl., 2s Qd 1866- 



10673 LEEDS (Frank Henley, F.I.C ), and William John Atkinson BUTTEBFIELD : 

 ACETYLENE : a practical Handbook on the PRINCIPLES of its GENERATION and USE ; 2nd [latest] 

 Edition, enlarged, with 62 illustrations and 2 folding tables, large cr. 8vo. cl., 5s Qd (p. 8s Qd nett) 1910 



10874 LEEDS (Lewis W.) TREATISE on VENTILATION : showing the great Want of Improved 

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

 woodcuts, 8vo. hf. calf, or, hf. morocco (title stamped), 4s New York, 1876 



LEEKE (John) v. CATJS (No. 729), and FOSTER (No. 8051-2), ante. 



10675 LE FEBUflE (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 preserve their essential 

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

 with 8 folding copperplates, 2 parts in 1 vol. sm. 4to. old calf, rebacked (first title and laxt 2 II. 

 soiled ', and the former mounted) ; RARE, 1. 5s Tho. Ratdifft, 1664 



FIRST ENGLISH EDITION of this early treatise on theoretical chemistry. ' Premier ouvrage de ce genre. On sentait 

 depuis longtemps le besoin de reum'r en un corps de doctrine les materiaux disperses un peu partout. Le ' Traite de 

 Chimie ' de Lelevre repondait a ce besoin de 1'epoque ; et c'est ce qui en explique le succes.' F. Hoefer. 



10676 LEFEBUE-E de FOUBCY (Louis I2tienne) ELEMENTS de TRISONOMETRIE, 7 e Edition ; wilh 

 folding plate, 8vo. sewn, Is Qd r Mons, 1853 



10677 LECONS d'ALGEBRE, 6 e Edition, 8vo. cl., with auto, of Richard Congreve, Positivist 



(1818-1899), 2s 6rf 1850 



10678 LECONS de GEOMETRIE ANALYTIQUE, comprenant la Trigonometric Kectiligne et 



Spherique, etc., 5 e Edition ; with 11 folding plates, 8vo. hf. morocco neat, 3s J846> 



10679 ^ NEUVIEME EDITION ; with 11 folding plates, 8vo. cl., 3s Qd 1871 



LEFEVRE d'^taples (Jacques) v. FABER STAPULENSIS, no. 7736 ante. 



10680 LEG-ENDUE (Adrien Marie; F.R.S.) ELEMENTS de GEOMETRIE, avec des Notes ; premiere 

 edition ; with 11 folding plates, 8vo. old calf (rubbed), 5s 1 794 



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, 8vo. cl. (scarce), with auto, of T. R. Birk*. pr. 

 (1810-83), 12s Qd Edin., 1824 



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

 also by Carlyle, who was recommended to undertake the work by Sir David Brewster, F.R.S., and received for it 50. 



10682 THEORIE des NOMBRES, 3 e [LA MEILLEURE] EDITION [avec Appendice : Methodes 



nouvelles pour la Resolution Approchee des Equations Numeriques, etc. etc.] ; with folding plate, 

 2 vols. 4to. hf. calf (VERY RARE), 2. 15s Didot, 1830 



THE BEST EDITION, NOW EXCESSIVELY SCARCE. 'The third edition, issued in 1830, includes the results of his various 

 later papers, and still remains a standard work on the subject. It may be said 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 contiins 

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

 a*2 + by* + cz'2 = Q.'IV. W. R. Ball. 



1C883 : 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, 

 with numerous diagrams, 8vo. calf (binding worn), 2s Qd 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 (ZJolding), 

 and about 140 other illustrations, cr. 4to. cl., Qs (p. 105 Qd nett) Dundee, 1893 



10685 LEGOYT (Alfred) Le LIVRE des CHEMINS de FER Construits, en Construction et Projetes, on 

 STATISTIQUE GENERALE de ces Voies de Communication en France et a 1'Etranger, post 8vo. sewn 

 (scarce], 7s Qd 1845 



Including the UNITED STATES. Several English names are most delightfully transmogrified, sc. that early venture, never 

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

 which made Cardiff as the Toffvale. 



10686 LE GRAY (Gustave, peintre et photographiste) PHOTOGRAPHIE : Traite Nouveau, theorique 

 et pratique, des Precedes et Manipulations sur PAPIER SEC et HUMIDE, et sur VERRE au 

 Collodion et a PALBUMINE, premiere edition, roy. 8vo. sewn (SCARCE), 1. Is 



Lerebours et Secretan [1852] 



This work, besides being a resume 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 FREDERICK SCOTT ARCHER (1813-57) to the discovery of the 

 COLLODION PROCESS. The latter (according to D. N. B.) ' in 1850 successfully applied collodion to photography. . . . The 

 first account was published in the ' Chemist ' March 1851.' 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 rapport 

 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 1850 (q^v. infra). 



10687 PRACTICAL TREATISE on PHOTOGRAPHY, on PAPER and GLASS, translated by THOMAS 



COUSINS, post 8vo. (pp. 24), sewn (SCARCE), 10* Qd 1850 



In the appendix the author announces his invention of the collodion 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 10, mixed with sulphuric et,her, and afterwards saturated with collodion ', etc. etc. etc. P. 24. 



10688 PHOTOGRAPHIC MANIPULATION : the WAXED PAPER PROCESS, translated, 12mo. 



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



