HENRY SOTHERAN & CO., 140, STRAND, W.C, and 37, PICCADILLY, W. 169 



3375 O'DRISCOLL (Florence) Notes on the Treatment of Gold Ores, vnth 28 woodcuts, roy. 

 8vo. cL, 45 6f/ (p. 85 Qd nett) 1889 



3376 OGAN (Alfred) Railway Collisions Prevented, ivith 5 plates, 8vo. (pp. 54), sewn, with inscr. 

 to Boss D. Mangles, M.P., chairman of the East India Co., 8s 6d 1855 



An account not only of the first suggestion of tiie Block System, but of its automatic working by electricity, and of 

 electric communication between signalmen and drivers. The apparatus was invented by a Mr. Tyer, an electrical 

 engineer. The pamphlet is dedicated toCapt. R. H. Barlow, General Manager of the South Eastern Railway, which was 

 the first line to try the system, 



3:377 OOILBY (William, Trinity Coll., Cantab., F.G.S., M.R.i.A.) New Theory of the Figure of the 



E\RTH, considered as a Solid of Revolution ; founded on the Direct Employment of the 



Centrifugal Force, instead of the common principles of Attraction and Variable Density, diagrams, 



roy. 4to. (pp. 121), sewn, 5s 1872 



Directed against the fondness and towering pride of mathematicians, and their 'analytical shibboleth r^J.' 



3.37S OHM (Martin; brother of the electrician) The Spirit of Mathematical Analysis, and its 

 Relation to a Logical System, trans, [with Notice] by Alexander John Ellis, post 8vo. 

 boards, Ss 184.3 



This translation wa.H the first mathematical publication (his fli-st published work was one on Horse-taming as practise<l 

 by the Re<l Indians) of that remarkable man Albx^noer John Ei.lis, mathematician, philologist, 8i)elling reformer and 

 atlv(H'ate of phonetic spelling, historian of Old English pronunciation, and scientific musician. 



.3.379 OKEN (Lorenz ; Univ. Munich) Erste Ideen zur Theorie des LiCHTS, der FiNSTERNiss, der 

 Farhkn mid der Warmk, 4to. (pp. 46), seicn, 2s Qd Jena, 1808 



3380 OLBERS (Heinrich Wilhelm Matthias) Abhandlung liber die leichteste und bequemste 

 Methode die Rahn eines Cometkn aus eigenen Beobachtungen zu berechnen ; with copper- 

 plate, sm. 8vo. original boards, with autos. of Prof. M. W. Drobisch, 1825, and Prof K. B. 

 MoUweide, 1807 (rare), £1. \s Weiviar, 1797 



First Edition of this important work, first announcing the author's invention of a new method of computing the paths 

 of comets. 



'OUiers's method is still regarded as the moat expeditions and convenient in rases where absolute rigour is not required. 

 By its introduction, not only many a toilsome and thankless hour was spared, but workers were multiplied, and encouraged 

 in the prosecution of labours more useful than attractive.* — Agnes M. Clerke. 



3381 OLNEY (Edward, Univ. Michigan) First Principles of Algebra, cr. Svo. cl., 2s 6d (p. 6s) 



New York, 1885 



33S2 General Geometry and Calculus, ivith over 250 diagrams, 8vo. cl., 4s ibidem, 1884 



3383 [OPPEL (Friedrich Wilhelm v.)] Analysis Triangulorum ; with plates, 4to. sewn, or, 



boards, 4? Dresdce, 1746 



33S4 OPUSCULA OMNIA ACTIS Eruditorum Lipsiensibus inserta, necnon Epitomoe si qure 



Materia vel Criticis Animadversionibus celebriores, 1621-1700; with numerous copperplates, 3 vols. 



4to. old calf gilt (FINE COPY), with bookplate of Philip 2nd Earl Stanhope, F.E.S., £1. 10* 



Venetiis, 1740-1 

 Containing all the more important treatises published in the 'Acta Eruditorum Lipsiensia* between 16S0 and 1700, 

 including numerous contributions by Leibniz, Jean and Jacques Bernoulli, v. Leeuwenhoek, Hevellus, Flamsteed, 

 Huygens, Papin, Briggs, Halley, etc. etc. 



3385 ORCHARD (Thomas N., m.d.) The Astronomy of Milton's * Paradise Lost', with 5 plates 

 and 8 woodcuts, Svo. cl. {out of print), \Qs Qd 1896 



3386 ORD (William Miller, m.d.) On the Influence of Colloids on Crystalline Form and 

 Cohesion, 8 plates, and woodcuts, large 8vo. cl.. As (p. 8* Qd) 1879 



3387 ORDNANCE NOTES (Nos. 206-235) from the Ordnance Office, War Department, 

 Washington, D.C, with numerous plates, and woodcuts, folio, hf calf {title stamped), 8s Qd 



[Washington, 1882-3] 



.3388 ORMATHWAITE (Sir John Beam Walsh, first Lord) Astronomy and Geology Com- 



PAKKO, post 8vo. ///. calf neat {stamp on title), 3s 1872 



3389 ORFORD (Hemy) Modern Optical Instruments, and their Construction ; illustrated, 

 cr. Svo cl., \sQd 1896 



3390 [ORIGANUS, recte TOST (David)] Annorum Posteriorum XXX, incipientiuni ah A. Chr. 

 1625 et desinentium in annum 16.54, Ephemerides BrandenburgiC/E Ctclestinm Motuum et 

 Teniporum, summa diligentia in Luminaribus Calculo Duplici Tychonis et Prutenico, in reliquis 

 Planetis Prutenico seu Copernieaio elaboratce ; with woodcuts, thick 4to. old calf {wanting title 

 and 9 preliminary lines), Ms Qd Francofurti ad Viadrum, 1609 



3.391 ORLANDI (Giuseppe) Tacheometria: Corso pratico di Topografia Nuraerica, 2'ift Edizione ; 

 illustrated, sq. Svo. cL, As Qd Torino, 1896 



3392 ORR'S Circle of the Sciences : Treatises on the Principles of Science, with their Application 

 to Practical Pursuits, with coloured maps, and numerous woodcuts and diagrams, COMPLETE in 

 9 vols, large post Svo. hf. calf extra {nice set), \bs (p. £2. 5« Qd in cl.) }^^^'^ 



CoNTKNTs:— I. Physiolocy and Anatomy, by Sir R. Owen, R. L. Latham, et«. : IT. Mathematical Sciences by J. K. 

 Young, J. F. Twisden. etc. : III. and VI. Zoology and Botany, by E. Smith and W. S. Dallas : IV. Elementary Chemistry, 

 by J. Scptfern : V. Geology and Mineralogy, by D T. Ansteil, J. Tennant, etc. : VII. Practical Astronomy and Meteorology, 

 by J. R. Young, E.J. Lowe, etc.: VIII. Practical Chemistry, by J. Scofferii, etc.: IX. Mechanical Philosophy, by W. 

 Mitx'hell, J. R. Young, eic. , . 



3393 Vol. II : The Mathematical Sciences, by J. R. Young, J. F. Twisden, pr., and Alex. 



Jardine, diagrams. Svo. cl., 2s 1^^* 



3394 Vol. IV : Geology and Physical Geography, Mineralogy and Crystallography, 



illustrated, Svo. cl., 2s 1^^" 



3395 Vol. V ; Nautical and Practical Astronomy, and Meteorology, illustrated, 8vo. 



cl.,2s \iw 



M 



