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3375 O'DBISCOLL (Florence) NOTES on the TREATMENT of GOLD ORES, with 28 woodcuts, roy. 

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3376 OGAN (Alfred) RAILWAY COLLISIONS PREVENTED, with 5 plates, Svo. (pp. 54), sewn, withinscr. 

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

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3377 OGILBY (William, Trinity Coll., Cantab., F.G.S., M.R.I.A.) NEW THEORY of the FIGURE of the 

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Directed against the fondness and towering pride of mathematicians, and their 'analytical shibboleth *?.' 



3378 OHM (Martin; brother of the electrician) The SPIRIT of MATHEMATICAL ANALYSIS, and its 

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This translation was the first mathematical publication (his first published work was one on Horse-taming as practised 

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3379 OKEN (Lorenz ; Univ. Munich) ERSTE IDEEN zur THEORIE des LIGHTS, der FINSTERNISS, der 

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3380 OLBEBS (Heinrich Wilhelm Matthias) ABHANDLUNG iiber die leichteste und bequemste 

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3331 OLNEY (Edward, Univ. Michigan) FIRST PRINCIPLES of ALGEBRA, cr. Svo. cl., 2s Qd (p. 6s) 



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3382 - GENERAL GEOMETRY and CALCULUS, with over 250 diagrams, Svo. cl., 4s ibidem, 1884 



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

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3384 OPUSCULA OMNIA ACTIS ERUDITORUM LIPSIENSIBUS inserta, necnon Epitomse si quae 

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Containing all the more important treatises published in the 'Acta Eruditorum Lipsiensia' between 1680 and 1700, 

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3385 ORCHARD (Thomas N., M.D.) The ASTRONOMY of MILTON'S 'PARADISE LOST', with 5 plates 

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3386 ORD (William Miller, M.D.) On the INFLUENCE of COLLOIDS on CRYSTALLINE FORM and 

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3387 ORDNANCE NOTES (Nos. 206-335) from the ORDNANCE OFFICE, WAR DEPARTMENT, 

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3388 ORMATHWAITE (Sir John Beam Walsh, first Lord) ASTRONOMY and GEOLOGY COM- 

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3389 ORFORD (Henry) MODERN OPTICAL INSTRUMENTS, and their CONSTRUCTION ; illustrated, 

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3390 [ORIGANUS, recte TOST (David)] ANNORUM POSTERIORUM XXX, incipientium ab A. Chr. 

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3391 ORLANDI (Giuseppe) TACHEOMETRIA : Corso pratico di Topografia Numerica, 2 da Edizione ; 

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3392 ORR'S CIRCLE of the SCIENCES : Treatises on the Principles of Science, with their Application 

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3393 VOL. II : The MATHEMATICAL SCIENCES, by J. R. YOUNG, J. F. TWISDEN, pr., and ALEX. 



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