contents; rii 



APRIL>1811. 



Engravings of thfi following Subjects: I. Two new Constructions of the Air 

 Pump. 2. Dissections of Plants, showing the Growth of the Bud, by Mrs. A, 

 '•Ibbetson. 



I. Observations and Experiments on the Alkaline Metalloids: by J. Murray, 

 LeCt^irer on Chemistry, &c., Edinburgh - - "241 



II. Cheap and simple Construction of an Air Piimp. In a Letter from a' Corre- 

 spondent - - - - - ■■■r^ r. f:0^1f 



III. On the Interior of Plants. Letter!. By Mrs. Agnes Ibbetson- ''254 



IV. Observations on the Oxides of Iron, with a Discussion of their Nature, 

 By Mr. J. H. llassenfratz - - - - 266 



V. On the Paj-ts of Trees primarily impaired by Age. In a Letter from T. A. 

 Knight, £sq. F. R. S. to the Right Hon. Sir Joseph Banks, Bart. K. B. 

 P. R. S. _ - , - - • - 275 



VI. Remarks on Mr. Dalton's Hypothesis of the Manner in which Bodies com-^ 

 bine with each other, in a Letter from John Bostock, M. D. - 280 



'VII. Effect of Changes in the State of the Atmosphere on Mr. De Luc's Elec- 

 '" trie Column. Communicated by Thomas Forster, Esq. - 293 



yill. On the Nature of Oximuriatic Acid, in Reply to Mr. J. Davy. By J. 

 iyiurray. Lecturer on Chemistry, Edinburgh - - 294 



JX. On the "Production' of the Hyperoxi muriate of Potash, considered with 



respect to Mr. Davy's Ideas of the Nature of Oximuriatic Acid. In -a Letter 



•* 'from a Correspondent ''^ '<— - - - - 310 



X. Observations respecting the Irritability of the Barberry, Berberis communis. 

 ^ By Mr. Robert Ly^U, Surgeon, Member of the Royal Physical Society of 



Edinburgh, and corresponding Member of the Literary and Philosophical 

 Society at Manchester. Communicated by the Author - 314 



XI. Extract of a Letter from the Rev. John Brinckiey, D. D. F. R. S. An- 

 drews Professor of Astronomy in the University of JDubliD^ to the Rev. 

 Nevil Maskelyne, D. D. F. R. S. Astronomer Royal, on the anntial Parallax 

 of a Lyrae - • - ' - - 317 



Scientific News. • - - . • * ibid. 



Meteorological Journal • - - .^ ^QQ 



SUPPLEMENT 



