HENRY SOTHERAN & CO., 140, STRAND, W.C., AND 37, PICCADILLY, W. 9,1 



1841 HEATHER (J. F., R.M.A., Woolwich) MATHEMATICAL INSTRUMENTS : their Construction, etc. ; 

 enlarged Ed., with numerous illustrations, 3 vols post 8vo. in 1, cl., 2s "' .* : 1877 



1842 HEA.VISIDE (Oliver, F.R.S.) ELECTRICAL PAPERS, with diagrams, 2' volsr large -8vo.% cl. 

 (SCARCE), 1. 15s ,1892 



A collection of the author's voluminous and important papers, originally issued in the Electrician, on Electromagnetic 

 Waves and Surface Conduction. 



1843 HEBERT (Luke, C.E.) The ENGINEER'S and MECHANIC'S ENCYCLOPEDIA, new.. Ed.,. with con- 

 siderable Additions, plates, and over 2000 woodcuts, 2 thick vols. 8vo. (pp. 1734), cl.; 6s ad 1849 



Of historical interest in connexion with general and Railway engineering, and all departments, of industrial chemistry. 



1844 HEIS (Eduard; Munster] ATLAS COELESTIS Novus : Stellae per Mediam Europam Solis Oculis 

 conspicuae secundum veras Lucis Magnitudiues e Coelo ipso descriptae, post 8vo. ; with Atlas, 

 containing 12 large star-maps, oblong folio 2 vols. cl. (SCARCE),. 1. Is Colonice, 1872 



'Besonders beriihmt ist sein Atlas coelestis novus, in welchem alle mit blossem Ange sichtbaren Sterne aufgenommen 

 ttm&.'Brockhaus's Konv.-Lex. ' While engaged on his great atlas, he attentively determined the change of magnitude of 

 stars visible to the naked eye ; and by means of the naked eye, the opera glass, and 'a fe'inall telescope, 'he. amassed a large 

 number of observations.' H. Macpherson. 



1845 HELIE (Felix) TRAITE de BALTSTIQUE EXPERIMENTALE ; Expose des principles Experiences 

 d'Artillerie executeesa Gavre de 1830 a 1864 ; with diagrams, 8vo. hf. calf, 4s (p. F. 12. sewn) 1865 



1846 HELLER (August, Budapest) GESCHICHTE der PHYSIK von Aristoteles bis auf die neueste 

 Zeit, 2 vols. roy. bvo. hf. calf gilt, 1. (p. M. 27. unbound) Stuttgart, 1882-4 



One of the best histories of physics published. 



1847 HELL INS (John, pr. ; F.R.S.) MATHEMATICAL ESSAYS on Several Subjects : containing NEW 

 IMPROVEMENTS and DISCOVERIES in the Mathematics, 2nd Ed., 4to. sewn (rare},.\'2s Qd 1789 



Comprising the following important papers, originally published in the ' Philosophical Transactions', and now revised 

 and enlarged : On the Computation of Logarithms : On the Reduction of Equations having t wo-'equal Roots : On the 

 Correction of Fluents found by Descending Series: O n, the Transformation of certain Series to others of Swifter Conver- 

 gency : On the Force of oscillating Bodies on their Centers of Suspension. 



1848 HELLYER (S. Stevens) The PLUMBER and SANITARY HOUSES. : a Practical Treatise on Internal 

 Plumbing Work, 6th [last] Ed., with 24 plates, and 333 woodcuts, roy. 8vo. cl.., 7s (p. 12s Qd) 1900 



'The best treatise existing on practical plumbing' (The Builder), describing the domestic arrangements of the not 

 remote past with a horrible directness. 



1849 HELM (Georg) DieENERGETiKnachihrer GESCHICHTLICHENENTWICKELUNG ; with diagrams, 

 8vo. cl. (fresh copy], out of print, 10s Leipzig, 1898 



1850 HELMHOLTZ (Hermann Ludwig- Ferdinand v.) HANDBUCH der PHYSIOLOGISCHEN 

 OPTIK ; ivith 11 plates, and 213 woodcuts, th.ickroy.8vo. calf (stamp on title), \8sQd Hamburg, 1867 



FIRST EDITION of the author's most important work, the first systematic treatise applying physical laws to the study 

 of the physiology of the eye, and equally valuable for the original discoveries and the historical investigations it contains. 



1851 - POPULAR LECTURES on SCIENTIFIC SUBJECTS, trans, by E. ATKINSON, with Intro, by 

 JOHN TYNDALL, F.R.S., BOTH SERIES, with woodcuts, 2 vols. large post 8vo. cl., 7s Qd (p. 15s) 1881 



1852 - FIRST SERIES ONLY, woodcuts, large post 8vo. cl., 3s Qd 1873 



1853 - - On the SENSATIONS of TONE as a PHYSIOLOGICAL BASIS for the THEORY of Music ; 2nd 

 English Edition, trans., thoroughly revised, and corrected, with numerous Notes, and New Appendix 

 to 1885, by ALEXANDER J. ELLIS, F.R.S. [philologist] , with woodcuts, etc., roy- 8vo. cl., 1. Is 1885 



This standard work contains the author's numerous discoveries in physiological acoustics. 



1854 - - VORLESUNGEN liber die ELEKTROMAGNETISCHE THEORIE des LIGHTS, herausgeg. v. 

 ARTHUR KONIG und CARL RUNGE ; with 54 woodcuts, roy. 8vo. hf. brown morocco gilt, cl. sides (as 

 good as new), 14s Hamburg, 1897 



1855 - : BOIS-REYMOND (Emil du) HERMANN VON HELMHOLTZ : Gediichtnissrede, 8vo. sewn, 

 Is Qd Leipzig, 1897 



1856 - : KCENIGSBERGER (Leo) HERMANN VON HELMHOLTZ, trans, by FRANCES A. WELBY, with 

 Preface by LORD KELVIN, and Bibliography, with 2 photogravure portraits after Lenbach, and 

 another cet. 27, 8vo. cl., 11s (sells 16s nett) Clarendon Press, Oxford, 1905 



1857 HELMONT (FranqoisMercureBaronvan) ALPHABETI vere NATURALIS HEBRAICI brevissima 

 Delineatio, qua} simul METHODUM suppenditat, juxta quam qui SURDI nati sunt sic informari 

 possunt, ut non alios saltern LOQUENTES INTELLIGANT, sed et ipsi ad Sermonis Usum perveniant ; 

 with front. andSQ plates illustrating the phonetics of each letter, 24mo. vellum, 10s Qd Sulzbaci, 1667 



' Curieux et rare.' Brunei. It is one of the earliest treatises on the physiology of phonetics, and on lip-language. 

 Bound np is 'Tractatus Physici, I. De Corporis et Mentis distinctione. II. De Loquela a D. DE CORDEMOV. Latine 

 versi a J * *C***., Genevce, 1679.' 



1858 HELMONT (Jean Baptiste van) ORTUS MEDICINE, i. e. Initia Physicse Inaudita. Progressus 

 Medicinae Novus, in Morborum Ultionem, ad Vitam Longam, edente FRANCISCO MERCURIO VAN 

 HELMONT, cum ejus Prsefatione ; with portrait of author and editor, thick sm. 4to. old vellum 

 (title slightly mended), 1. Is Amst., Lud. Elzevirius, 1648 



FIRST EDITION of the author's complete works. 



1859 - EDITIO NOVA, cumque locupletiori Rerum et Verborum Indice, adauctior et exornatior; 

 ivith portrait, thick sm. 4to. sound copy in old calf, 18s Qd ib., a. e., 1652 



'He is regarded by some historians of chemistry as the greatest chemist who preceded Lavoisier. He was the first to 

 point out the imperative necessity for employing the balance in chemistry, and by its means showed in many instances 

 the indestructibility of matter in chemical changes. He was the first to apply the term gases to elastic aeriform fluids. 

 He was also the first to take the melting-point of ice and boiling-point of water as standards for the measurement of tem- 

 perature. It is in his work that the term saturation is first employed ', etc. etc. etc. 



1860 HELSHAM (Richard, M.D., Prof. Nat. Phil. Dublin, friend of Dean Swift) LECTURES in 

 NATURAL PHILOSOPHY, published by BRYAN ROBINSON, M.D., with 11 plates, 8vo. old calf (nice 

 copy), with bookplate of Philip 2nd Earl Stanhope, F.R.S., Gs Qd 1739 



1861 SECOND [LAST] EDITION, with 11 plates, 8vo. old panelled calf, Qs 1743 



The appendix contains original problems : ' Of the collision of Non Elastick and Elastick Bodies ', etc. etc. 



