TO CORRESPONDENTS. 



Communications have been received from Mr.DAViES, on the Properties 

 6f the Trapezium ; and from Mr. Bywater, on Microscopic Observations. 



PHARMACOPOEIA LONDINENSIS, 



Iterum recognita et retractata, 1824', p. 6. 

 "ACIDUM ACETICUM FORTIUS," 

 vel 

 " Acidum Aceticum e Ligno destillatum." 



PURE CONCENTRATED ACETIC ACID, agreeable to the Sample 

 furnished at the request of the Committee of the Royal College of 

 Physicians, may be had of the Manufacturers, BEAUFOY & CO. South 

 Lambeth, London. 



ENGRAVINGS. 



Vol. LIII. A Plate illustrative of Dr. Urs's Experiments on Caloric, 

 Mr. Luckcock's Paper on the Atomic Philosophy, and Mr. Bolton's 

 on the Purification of Coal Gas. — A Plate representing Mr. Rennie's 

 Apparatus emplr'yed in his Experiments on the Strength of Materials; 

 and the Marquis RiDOLP Hi's Improvement on the Gas Blow-pipe. — A 

 Plate illustrative of Mr. Meikle's Paper on Calorific Radiation; Mr. 

 Lov/i's on the Purification of Coal Gas; and Mr. Hughes's on ascer- 

 taining Distances. — A Plate illustrative of Dr. Olinthus Gregory's 

 Paper on the different Rates of Pennington's Astronomical Clock at the 

 Island ofBalta, and at Woolwich Common. 



Vol.LIV. A Plate illustrative of the Menai Bridge. — A Plate illus- 

 trative of Mr. Lowe's Description of a Mercurial Pendulum. — A Plate 

 illustrative of Mr. Hare's Calorimotor, a new Galvanic Instrument — A 

 Plate illustrative of Captain Sabine's Paper on Irregularities observed in 

 the Direction of the Compass Needles of the Isabella and Alexander in 

 the late Voyage of Discovery ; and Mr. Scoresb's Anomaly in the Va- 

 riation of the Magnetic Needle as observed on Ship-board. 



Vol. LV. A Plate exhibiting a Sketch of the Comet's Path of July 1819. 



A. Plate illustrative of the Annular Eclipse of the Sun on the 7th of 



September next. — A Plate illustrative of Mr. Lane's Instrument for 

 gathering Fruit; Mr. Young's Mode of preparing Opium from the 

 Papaver somniferum; and of Captain Forman's Essay on a Property in 

 Light which hitherto has been unobserved by Philosophers. — A Plate de- 

 scriptive of Mr. Cuthbert's improved Hydro-pneumatic Apparatus, &c. 

 —A Plate illustrative of Capt. Forman's Essay on the Reflection, Refrac- 

 tion, and Inflection of Light/&c. ; and Mr. Charles Bonnycastle's 

 Communication respecting the Influence of Masses of Iron on the Mari- 

 ner's Compass. 



Vol. LVI. A Plate illustrative of Mrs. Ibbetson's Paper On the Phy- 

 siology of Botany. — A Plate illustrative of Mr. Hall's Percussion Gun- 

 Lock; of Dr. Kitchiner's Pancratic Eye-Tube ; and of Mr. Park's 

 Mooring Blocks.— A Plate exhibiting Sections, &c. of Mr. Malam's im- 

 proved Gas-Meter. — A. Plate exhibiting the Discoveries made by Capt. 

 Parry in the Polar Sea. 



Vol. LVII. A Plate illustrative of Mess. QErsted and Ampere's 

 Electro-magnetic Experiments, and Mr. Perkins's Paper on the Com- 

 pressibility of Water.-»-A Plate illustrative of Mr. Jamieson's Marine 

 Thermometer Case, and Mr. Jenning's Mercurial Log-Glass. — A Plate 

 illustrative of Dr. Hare's new Modification of Galvanic Apparatus. — A 

 Plate representing a Double Canal Lock, originally proposed for the Re- 

 gent's Canal, by Mr. R. H. Gower ; and a Modification of Electro-mag- 

 netic Apparatus, by Mr. Tatum. 



