HENRY SOTHERAN & CO., 140, STRAND, W.C, and 37, PICCADILLY, W. 93 



1841 HEATHEB (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 HEaVISIDE (Oliver, f.r.s.) Electrical Papers, with diagrams^ 2 vols, large 8vo. cl. 

 (SCARCE), £1. 15s 1892 



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

 Waves and Surface Conduction. 



1843 HEBERT (Luke, c.E.) The Engineer's and Mechanic's ENCYCLOP.^£DIA, new Ed , with con- 

 siderable Additions, plates, and over 2000 woodcuts, 2 thick vols. 8vo. (pp. 1734), cl., Qs iid 1849 



or hist<:)iical interest in connexion with general and Railway engineering, and all departments of industrial cliemistry. 



1844 HEIS (Eduard; Miinster) Atlas Coelestis Novus : Stellae per Mediam Europani Solis Oculis 

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

 containinrj 12 large star-maps, oblonjjj folio— 2 vols. cl. (SCARCE), £1. Is Colonic, 1872 



' IJesonders beruliint ist sein Atlcw coelestis tiovus, in welchoni alle niit blos.seni Auge sichtbaren hterne aufgeuomnien 

 siml.'—liruckhitus's Konv.-I.ex. ' While engaged on his great atlas, ho attentively determined the change of magnitude of 

 stars visible to the naked eye ; and by means of the naked eye, the oi»era glass, and a small telescoiK*, lie amassed a Uirge 

 numl»er of observations," — //. Macphergjn. 



1845 HELIE (Felix) Traite de Balistique Experimextale ; Expose des principales E.xperiences 

 d'Artilierie executeesh, (Ifivre de 1830 ^ 1864 ; with diagrams, 8vo. hf. calf^ 4s (p. F. 12. sewn) 1865 



1846 HELLER (August, Budapest) Geschichte der Physik von Aristoteles bis auf die ncueste 

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



One of the best liistories of physics published. 



1847 HELLINS (John, or. ; F.R.S.) Mathematical Essays on Several Subjects: containing New 

 Improvements and Discovekies in the Mathematics, 2nd Ed., 4to. sewn (rare), \2s 6d 1789 



Comprising the following important papers, originally published in the ' Philosophical Transactions', and now revi.sed 

 and enlarged: On the Computation of Logarithms: On the Reduction of Equations having two eijual Roots: On the 

 (Correction of Fluents found by Descending Series : On the Translonr.ation of certain Series to others of Swifter Couver- 

 gency : On the Force of o.scillating B«j<lie3 on their Centers of Suspension. 



1848 HELLTEB (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, Is (p. 12* Qd) 1900 



'The best treatise existing on practical plumbing ' (77m; Bui.der), describing the domestic arrangements of the not 



remote past with a horrible directness. 



)849 HELM (Ge org) DieENERGETlKnach IhrerGESCHICHTLICHENENTWlCKELUNG ; with diagrams, 



8vo. cl. {fresh copy), out of pi'int, \Qs Leipzig, 1898 



1850 HELMHOLTZ (Hermann Ludwig Ferdinand v.) Handbuch der physiologischkn 



Ol'TlK ; irith 11 plates, and 2\^ woodcuts, thick roy. 8vo. calf {.stamp on title), 18s 6fl^ Hamburg, 1867 



FiK.sT Edition of the author's most important work, the first systematif» treatise applying physical laws \m 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 Tvndall, f.r.s., both series, with woodcuts, 2 vols, large post 8vo. cl.. Is 6d (p. 15*) 1881 



1852 EiRST Series only, woodcuts, large post 8vo. cl., 3s 6rf 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.,£l. Is 1885 

 This standard work contains the authors numerous discoveries in physiological acoustics. 



1854 Vorlesungen iiber die elektromagnetische Theorie des Lights, herausgeg. v. 



Arthur Konig und Carl Kunge ; with 54 woodcuts, roy. 8vo. hf. brown morocco gilt, cl. sides {as 

 good as fiew), lis Hamburg, 1897 



1855 : Bois-Keymond (Emil du) Hermann von Helmholtz : Gedjichtni.ssrede, 8vo. seirn, 



Is 6d Leipzig, 1897 



1856 : Kienigsberoer (Leo) Hermann von Helmholtz, trans, by Frances A. Welby, with 



Preface by Lord Kelvin, and Bibliography, with 2 photogravure portraits after Lenbach, and 

 another a't. 27, 8vo. cl.. Us (sells 16* nett) Clarendon Press, Oxford, 1906 



1857 HELMONT (Fran9oi8 Mercure Baron van) Alphabeti vere Naturalis Hebraici brevissima 

 Delineatio, ([u;v sinnil Methodl .M suppenditat, juxta quam qui SURDI nati sunt sic informari 

 possunt, ut non alios saltern LOQUENTES intelligan T, se<l et ipsi ad Sermonis Usum perveniant ; 

 with front, and '^^ plates illustrating the phonetics of each letter, 2\\\\o. vellum, 10*6rf Sulzbaci, 1667 



'Curieux et rare.' — /.'r«ne^ It is one of the earliest treatises on the pliysiology of jihonetics, and on lip-languagt;. 

 Bound up is 'Tractatus Physici, I. De Corp<;>ris et Mentis distinctione. II. De Lofpiela a D. dk Cokdemov. Latine 

 versi h J * * * C * * *., Genevte, 1679.' 



1858 HELMONT (Jean Baptiste vaji) Ortus Medicix.e, i. e. Initia Physiwe Inaudita. Progressus 

 Medicinie Novus, in Morborum Ultionem, ad Vitam Louf'am, edente Francisco Mercurio van 

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

 (title slightly mended), £1. \s Amst., Lud. Elzevirius, 1648 



FiR-sT Edition of the author's complete works. 



1859 Editio Nova, cumque locupletiori Renim et Verborum Indice, adanctior et exornatior; 



with portrait, thick sm. 4to. sound copy in old calf, 18s 6d ib., a. e., 1652 



'lie is reganlcd by sonie historians of chemistry as the greatest chemist who preceded Lavoisier. He was the first to 

 l)oint out the imperative necessity for employing the balarce 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 riases to elastic aeriform fluids. 

 He was also the first to take the melting-point of ice and boiling-point of wat<!r 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 Kobinson, m.d., with 11 plates, 8vo. old calf {nice 

 copy), with bookplate of Philip 2nd harl Stanhope, F.R.S., 6* Qd 1739 



1861 Second [last] Edition, with 11 plates, 8vo. old panelled calf, 6* 1743 



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



