HENRY SOTHERAN & CO., UO, STRAND, W.C, aiJd 37, PICCADILLY, W. 369 



7226 DEMACHY (Jacques Francois) Laborant im Grossen, oder Kunst die cheuiischen Produkte 

 fabrikmiissig zii verfertio;en, mit Anmerkiingen von Heinrich Struve iind einer Abhandlung von 

 J. C. Wiegleb; iibersetzt und mit Zusiitzen versehen von Samuel HAHNEMANN; with 8 copper- 

 plates, 2 vols. 8vo. sewn, Qs Leipzig, 1784 



Interesting as being translated by the founder of homcjeopathy. 



7227 DEMINNE (Edmond) Solution du Probleme de la Navigation Aerienne : le Ballon 

 Deminne ; with plate, 8vo. (pp. 32), sewn {scarce), 10* Qd Bruxelles, 1865 



Deniinne's balloon was remarkable as combining the fundamental bases of the dirigible and aeroplane of the present 

 day. It contained six screw-propellers, two horizontal wings to give it stability, and two vertical ones acting as rudders, 

 while moveable weights were to cause the balloon to ascend or descend. 



7228 DEMPSEY (G. Drysdale, c.e ) The Machinery of the Nineteenth Century, 25 large plates, 

 roy. folio, with Text, 4to.— 2 vols. cl. cover, 6.v ' [1852-6] 



Including steam-ploughs and farm machinery, printing machines, and Crampton's odd locomotive with drivers worked 

 from an intermediate wheelless crank-axle, which nevertheless made 73 miles an hour on the S. E. W. 



7229 Malleable Iron Bridges, with lithographic view, and 10 folding plates: Brick 



Bridges, Sewers, and Culverts, 10 folding plates {one I. defective) : Timber Bridges and 

 Viaducts, \Q folding plates-. Iron Bridges, \Q folding plates : Moving Bridges, Iron, 

 Suspension, and Oblique Bridges and Viaducts, 10 folding plates : Iron Roofs, 20 folding 

 plates, 2 V. : Stations, Engine-Houses, Manufactories, Warehouses, Workshops, etc. etc., 16 

 folding plates : Iron applied to Railway Structures, 10 plates— 9 pieces in 1 vol. 4to., and 

 2 vols, folio and inipl. folio, containing the plates— tog^iXiev 3 vols. hf. calf,£\. 15a* (p. £13. 13a') 1850-6 



7230 DENNY (George A.) The Deep-Level Mines of the Rand, and their Future Development 

 con.sidered from a Commercial Point of View, with 4 folding plates, and 44 woodcuts, impl. 8vo. 

 buckram, H)s iSd (p. £1. os nett) 1902 



7231 The Klerksdorp Gold Fields : a Description of the Geologic and Economic Conditions 



obtaining in the Klerksdorp District, S.A.R. ; with 6 large folding plates, and 2 large folding maps 

 in pocket, inipl. 8vo. cl., \0s ^kl (p. £2. 2.y nett) 1897 



7232 DENT (Edward John, f.r.a.s.) Description of the Dipleidoscope, or Double-Reflecting 

 Meridian and Altitude Instrument ; with plain Instructions for using it in the Correction of Time 

 Keepers, ivith woodcuts, 8vo. (pp. 24), sewn, Zs apud auctorem, 1845 or '52 



7233 , Paper on the Patent Azimuth and Steering Compass, invented by, 8vo. (pp. 7), 



sewn, 2s apud eundem, 1844 



7234 Treatise on the Aneroid, a newly invented Portable Barometer, with short 



Historical Notice on Barometers in General, their Construction and Use, woodcuts, 8vo. (pp. 34), 

 sewn. 3.9 a. e., 1852 



7235 DERHAM (William, d.d., Canon of Windsor; Pres. St. John's Coll., Oxon. ; F.R s.) Astro- 

 Theology : or a Demonstration of the Being and Attributes of Goo, from a Survey of the 

 Heavens, 8th Ed., with 3 copperplates, 8vo. old calf, with auto, of Thomas Langley, pr., topo- 

 grapher (1769-1801), 4* 1741 



72.36 Physico-Theology : or a Demonstration of the Being and Attributes of God, from 



his Works of Creation, with large Notes and many curious Observations, 8th Ed., 8vo. old calf 

 (nice copy), 5s 6d 1732 



' It shows much reading as well as iiminions observation, and is a .statement of the argument from final causes. Paley 

 used it and occasionally refers to it.'— ^i/ lj<Ue Stephen. 



7237 DESAGULIERS (John Theophilus, Chaplain to the Duke of Chandos, f.r.s.) Course of Ex- 

 I'EKIMENTAL PHILOSOPHY, first edition, with IS fine copperplates, 2 vols, 4to. old calf gilt {not 

 quite imifonn) ; RARE, £1. Is 1734-44 



' Desagulien: is the only writer of the period who attempts to give a detailed account of the early history of Newcotnen's 

 invention [the atmo.spheric engine] in the .second vol. of his Course of Experimental Philosophy'. — ({allon-oy. He invented 

 a steam engine (a Savery engine with a lever safety valve), and a number of improvements therein, which are also 

 described in the above work. 



Among many other things of great interest, the work contains a proposition of the impossibility of perpetual motion, 

 and a description of his invention of a machine called the planetarium, ' which served to determine the exact distances of 

 the heavenly bodies according to the systems of Newton and Copernicus. He aLso erected a ventilator in a room over the 

 House of Commons ' (D. N. 7J.)— the prolitic parent of many .successive extractors of public money, if not of bad air. 



7238 Dissertation concerning Electricity, with a Letter from President Barbot, of the 



Academy of Bordeaux, 8vo. (pp. 50), sewn (RARE), 12* 6d 1742 



This pamphlet, which received the prize of the Bordeaux Academy, is imiwrtant as originating the term ' conductors ' 

 and 'non-conductors ' (called ' electricks and non-electrioks j)fr .St-'), and contains numerous experiments in illustration. 

 There are also interesting experiments on electric attraction and repulsion, and at end, a chapter ' concerning the several 

 Authors who have treated of Electricity.' 



7239 Physico-Mechanical Lectures, or Account of what is K-xplaind and Demonstrat'd in 



his Course of Mechanical and Ex])erimental Philosophy, wlierein the Principles of Mechanics, 

 Hydrostatics, and Optics, are demonstrated and explained by a great number of Experiments : 

 Vream (William, pneumatical instrument maker) DESCRiPTioN of the AiR-PuMP, according to the 

 late Mr. Hawksbee's best and last Improvements ; with the Manner of making Fifty of the most 

 curious Experiments upon it ; with 2 fine folding copperplates — 2 vols. 8vo. in 1, sound copy in old 

 calf {rare), \0s Qd 1717 



7240 Another Copy of Both Works, interleaved throughout with writing paper, 2 vols. 8vo. 



in 1, fine copy in contemporary sprinkled calf gilt, \5s 



' He is said to have been the first to deliver lectures on learned subjects to the general public. They were attende<l by 

 the most learned men of the day, and were made interesting by skilful experiments.'— D. N. B. The Prince of Wales, 

 afterwards George II., and Queen Caroline weie regular frequenters. 



The author was the son of a Huguenot pastor at La Rochelle, and was brought to England on the Revocation of the 

 Edict of Nantes hid in a tub. After receiving Holy Orders he became chaplain to 'the Princely Chandos ' and vicar of 

 Little St.anmon\ Mi'l<ilt-;>'X, \vlnn' Hamirl played tlie orirau wliicli still exists there. 



