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



6121 BELLI (Silvio, Vicentino) Delia PROPORTIONE, et PRO PORTION ALIT A Communi Passioni del 

 Quanto Libri III utile e neccessarij alia vera, e facile Intelligentia dell' Arithmetica, della 

 Geometria, e di tutte le Scientie et Arti ; handsomely printed in italics, with woodcut initals, sni. 

 4to. boards (FINE AND LARGE COPY) ; RARE, 18s Qd " Venetia, F. de' Franceschi Sanese, 1573 



Bellissimaedizione ... La materia trattata in qnesta operetta e in sostanza il quinto libro di Euclide, il quale ordinato 

 nel modo che all' autore parve piu conveniente, retiene egli doversi premettere allo studio delle matematiche.' Riccnnll. 



6122 QUATTRO LIBRI GEOMETRICI, il Primo del MISURARE con la VISTA, nel quale s'insegna, 



senza travagliar con Numeri a misurar facilissimamente le Distantie, 1'Altezze, e la Profondita, 

 con il QUADRATO GEOMETRICO, e con altre Stromenti, ecc. ; gli altri Tre sono della PROPORTIONE 

 e PROPORTIONALITY Communi Passioni del Quanto ; with numerous fine woodcuts, sm. 4to. 

 boards, 16s ib., R. Megietti, 1595 



' Raro. . . . Puo riescire di qualche utilita 1'esaminare i modi allora usati di misurare le distanze e le superfteie. II 

 nietodo del quale 1'autore fa cenno di rilevare la circonferenza della terra, e quello proposto anche dal Maurolico 

 (v. No. 2915, ante) ; cioe di dedurla dalla proprieta della tangente al cerchio di essare media proporzionale fra la secante, 

 e la sua parte esterna ; facendo coincidere la secante con tin diametro cerchio.' Riccardi. 



6123 BENJAMIN (Charles Henry, Case School, Cleveland) MODERN AMERICAN MACHINE TOOLS, 

 with 134 illustrations, 8vo. cl., 12s Qd (p 18s net) 1906 



6124 BENJAMIN (Park, PH.D.) The INTELLECTUAL RISE in ELECTRICITY, with etched portraits (of 

 Gilbert, Guericke, and Franklin), and 27 fs. illustrations from rare works, 8vo. cl. (out of print), 

 Is Qd (p. 1. Is) 1895 



An interesting history of electrical science from the earliest times to Benjamin Franklin, by an eminent American patent 

 lawyer. 



6125 BENNET (Abraham, Curate of Wirksworth, F.R.S.) DESCRIPTION of a NEW ELECTROMETER, 

 in a Letter to the Rev. Joseph Priestley, LL.D., F.R.S., with APPENDIX, 3 folding plates by Basire, 

 4to. (pp. 9), sewn, 10s 6d 1786 



The first account of the author's discovery of the gold-leaf electroscope. Added are three further papers, viz. : Account 

 of a New Comet, by CAROLINE HERSCHEL : Remarks on the New Comet, by SIR WILLIAM HERSCHEL, with plate : 

 Magnetical Experiments and Observations, by TIBERIUS CAVALLO, F.R.S. 



6126 A NEW SUSPENSION of the MAGNETIC NEEDLE, intended for the Discovery of Minute 



Quantities of Magnetic Attraction : also an Air Vane of great Sensibility, with New Experiments 

 on the Magnetism of Iron Filings and Brass, with folding plate by Basire , 4to. (pp. 18), sewn, 

 5s Qd 1792 



6127 NEW EXPERIMENTS on ELECTRICITY, wherein the Causes of Thunder and Lightning, as 



well as the constant state of Positive or Negative Electricity in the Air or Clouds, are explained ; 

 with EXPERIMENTS on CLOUDS of POWDERS and VAPOURS artificially diffused in the Air ; also 

 DESCRIPTION of a DOUBLER of ELECTRICITY, and of the most sensible ELECTROMETER yet con- 

 structed ; with other New Experiments and Discoveries, 4 folding plates on copper, Svo. con- 

 temporary hf. calf, or, new hf. calf gilt (VERY SCARCE), 1. 10s Derby, 1789 



The author discovered the principle of doubling in electricity, by which the difference of potential between two con- 

 ductors is indefinitely increased, and which was immediately utilised by Nicholson in the invention of his ' revolving 

 doubler ' ; while he will always be known as the inventor of an electrical instrument still in daily use the gold-leaf 

 electroscope. 



It is therefore very surprising to find that no record whatever of him is contained in the Dictionary of National Biography. 



6128 BENNETT (John, C.E.) ORIGINAL GEOMETRICAL ILLUSTRATIONS ; or the Book of Lines, 

 Squares, Circles, Triangles, Polygons, etc. , showing an Easy and Scientific Method for increasing, 

 decreasing, and altering any given Circle, Squaie, Triangle, Ellipsis, Parallelogram, Polygon, etc. 

 to any other Figure containing the same Area, by plain and simple Methods, laid down agreeably 

 to Mathematical Demonstration, with 55 plates and numerous diagrams, 4to. cL, 8s 1837 



6129 BENT (William) METEOROLOGICAL JOURNAL of the Year 1803, kept in [Paternoster Row], 

 London, Svo. (pp. 16), sewn, 2s Qd 1804 



6130 BERG (F. J. van den) Over de BEREKENING van LIGGERS, doorgaande over meer dan twee 

 Steunpunten, met flaauw gebogen Lengteas, veranderlijke Dwarsdoorsnede en willekeurige 

 Belasting, 4to. (pp. 9), sewn, Is Qd 's Gravenhage, 1873 



6131 Over de GRONDFORMULEN voor de DOORBUIGING van een veerkrachtig staafvormig 



Ligchaam ; with plate, 4to. (pp. 15), sewn, 2s ib., 1876 



6132 Over het DRAAGVERMOGEN van een aan beide Einden Bevestigd Prisma, 4to (pp. 18), 



sewn, 2s ib., 1875 



6133 Over het THEOREMA der DRIE REACTIEN bij een DOORGAANDEN LIGGER met STEUN- 

 PUNTEN op Ongelijke Afstanden, 4to. (pp. 7), sewn, Is Qd ib., 1890 



6134 BERGBOHM (Julius) NEUE RECHNUNGSMETHODEN der HOHEREN MATHEMATIK, 8vo. sewn, 

 Is Qd Stuttgart, 1891 



6135 BERGER (Hugo) GESCHICHTE der WISSENSCHAFTLICHEN ERDKUNDE der GRIECHE'N, 4 vols. 

 Svo. in 1, handsomely bound in hf. polished brown morocco gilt, cl. sides, t. e. g., with Dr. Emil 

 Reich's bookplate, 12s Qd Leipzig, 1887-93 



INHALT: Geographic der Jonier: Vorbereitungen fiir die Geographic der Erdkugel: Geographic der Erdkugel : 



der Griechen unter dem Einflusse der Romer. 



6136 BERGERON (L. E.) MANUEL du TOURNEUR : la Maniere d'executer sur le Tour a Pointes, a 

 Lunettes, en 1'Air, a Guillocher, Carre, a Portraits, h, Graver le Verre ; et avec les Machines 

 Excentriques, Ovales, Epicycloides, etc., avec ^Notions elementaires sur la CONNAISSANCE des Bois, 

 la Menuiserie, la Forge, la Trempe, la Fonte des Metaux, etc., 2 Ed., consideYablement augmented 

 par P. HAMELIN-BERGERON, 2 vols. 4to., with Atlas, containing 96 fine copperplates (mostly 

 folding, and 8 HAND-COLOURED ONES, showing 72 different specimens of wood), oblong 4to. 3 vols. 

 hf. calf gilt, with bookplate of Henry B. H. Beaufoy, F.R.S. (SCARCE), 1. 15s 1816 



Ouyrage fort estir..e ; la premiere edition, Paris, 1792-6, 2 vol., est bien inferieure a celle-ci. L. G. I. Salivet, avocat, 

 en a ete, dit-on, le redacteur.' Brunei. 



