TO CORRESPONDENTS. 



Want of room has compelled us to defer till next month some communications 

 which we had hoped to be able to give in the present number. 



Our Correspondent XX will hear from us within a few days. 



Mr. Wiseman's Paper on Dr. Young's Report on Improvements in Gauging has 

 come to hand, and shall receive attention. 



In the Number for February last, in Mr. Sturgeon's paper, page 97, line 17, for 

 " the platinum is positive to the silver," read " the silver is positive to the plati- 



"Tn'the Number for April, page 268, line 5, for "400°," read " 100°." 



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. 



THE SECOND NUMBER of the ZOOLOGICAL JOURNAL 

 will be Published on the 15th June by W. Phillips, George Yard, 

 Lombard Street. 



ENGRAVINGS. 



Vol. LI 1 1. A Plate illustrative of Dr. Ure'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 employed in his Expeiiments on the Strength of Materials; 

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

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

 Lowe'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. SrQRESBY's Anomaly in the Va- 

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



Vol. LV. A Plate exhibiting 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 Fiuit; Mr. Young's Mode of preparing Opium from the 

 Papaver somniftrum; md 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 Hydrq-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'j 

 Communicacion respecting" the Influence of Masses of Iron on the Mari- 

 ner's Compass. • 



