ENGRAVINGS. 
_ on Electro-chemical Agency —Mr. Accum’s New Mineralogical Apparatus. 
—Mr. Lez’s Thrashing Machine—Mr.Coox’s Apparatus for making Gas 
and other Products from Pit-Coal ; and Mr. Way’s Method of procuring 
Turpentine from Fir-Treés. —A Plate to illustrate Dr. Beswsrer’s Paper 
on the Power of the Lever. 
Vol. XXXVIIL. Mr. Donk in’sTachometer.—Mr. Aucan’s Mathematical 
Dividing Engine.—A 4to Pate of Mr. Lozscuman’s Patent Piano-Forte, 
and Mr. Lrston’s Patent Echarmonic Organ.—A Plate to illustrate Mr. 
Hauy’s Paper on the Electricity of Minerals.—Mr. Waiker’s improved 
Micrometer.— Mr. Moutr’s Vilte-ing A pparatus.—Mr.8mivn’s Method of 
relieving a Horse fallen in the Shafts of a loaded-Cart.— Mr. Jonn Taytor’s 
Air-Exhauster for Mines. —A Representation of the Comet now visibie iu 
Ursa Major.—Sir Howaxp Dovuctas’s Patent Reflecting Semicircle.— 
of the Earth occurring in Lancashire.—Mr. Sapter’s Apparatus’ for 
Smelting of Lead.—A Plate to illustrate Mr. Wittram Smitru’s and Mr. 
Epwakp Martin's Reports on the State of the Collieries at and near Nail- 
sea, in Somersetshire.—Mr. Sapver’s Apparatus for Smelting of Lead.— 
A Plate to illustrate the different Theories of Arches or Vau'ts,and of Domes. 
Vol. XXX1X. Mr. Sreevens’s New Levelling-Sta.-—A Map illustrating 
the Great Derbyshire Denudation.—A Quarto Plate to illustrate the Opti- 
cal Instrument ca'led the Diacatoptron,—A Plate of Mr. Sreevens’s 
Contrivance for freeing Water-pipes from Air: engraved by Mr. PorTER.— 
Mr. Atian’s improved Reflecting Circle-—Mr. Woon’s inclosed Grind- 
stone for Pointing Needles, and Mr. Wensrer’s Method of carrying off 
‘Steam from Boilers.—Mr. Bronton’s improved Pump for raising Water 
while Shafts or Pits are sinking—Mr. Hopngson’s improved Mariner’s 
Compass for correcting the Magnetic Variations.—A Quarto coloured Plate 
illustrate the Geology of Wart of the Vicinity of Dublin. 
_ Vol. XL. A Plate to illustrate the Foundation of Mr. Witx1aM Jonis’s 
‘temporary Corn Rick.—Mr. Srernens’s Method of dividing Bricks,— 
Section of Mr. Wirtram Jones's temporary Cora Rick.—Mr. WarsTeit’s 
Improvement on the Acorn Dibble.— A Plate to illustrate Mr. Tawney’s 
New Thrashing Machire.—fwo Octavo Plates Cescriptive of a New Ma- 
“chine for Pomping Water.— Two i lates descriptive of the Muscular Moe 
| tion of Snakes —Figures to illustrate such Portions of a Sphere as have 
their Attraction expressed by an algeb:aic Quantity—WVan Hetmont’s 
Differential Thermometer.—Formation of Ovals for Gardeners. —CHAVASsE’S 
Marine Transit.—A_ Plate to illustrate Mr. Brop:e’s Experiments on 
the Influence of the Brain on the Generation of Animal Heat. 
TeVol. XL. Pzrvs’s Mercurial Voltaic Conductor.—Lesiiz’s Did- 
ferential Thermometer. Diagrams’to illustrate Dr. Wortaston’s Peri- 
“scopic Carnera Obscura and Microscope.—Count Rumroxrn’s improved 
Coffee-pots.—Mr. Goss’s Instrument to work Addition of Numbers 
. Accuracy and Dispatch.—Mr, Davis’s hanging Scaffold; and 
Mr. Maxrin’s Method of relieving actiorse. from a Cart. when fallen 
: “in its Shafts— A Qnarto Plate to iustrate Mr. J. Hicks’s Ace 
unt of the Situation and Means of raising the Royal George.—A Plate 
strate Mr. Sournern’s Essay on the Equilibrium of a Combination 
eams, Blocks, &c. and on the Polygon of Forces.--A Plate to illustrate 
;Steevens’s Account of a Meteor seen at London and other Places in 
th Tast.—A ‘Plate to illustrate Mr. Macngcix.’s Annular Saw. 
Vol. XLU. A Plate containing Professor Lesxin’s Atmometer, and 
gures to illustrate Dr, Wottasvon’s Paper on the elementary Particles 
of cértain Crystals —A Sketch of that Part of the Island of Java which 
contains the natural Lake of Sulphuric Acid. 
Acoloured Map to illustrate Dr. Campgery’s Paper on the inferior Strata 
