INDEX. 445 



Hay, (E. W. A. Esq.) description of an ancient monument 

 found at Colchester, representing the Theban Sphinx, 1-17 



Heat, laws of the propagation of, 180 — observations on the 

 heat of the sun's rays during the solar eclipse of September 

 7, 1820, 313, 314 



Henry, (Dr.) on the aeriform compounds of charcoal and hydro- 

 gen, 134, 135 — experiments on the gases obtained from oil 

 and coal, 13.5 



Herculaneum, notices of Sir Humphry Davy's observations and 

 e.xperiments on the Papyri of, 367-369 



Herschcl, (J. F. W. Esq.) Sir Godfrey Copley's gold medal 

 awarded to, 300 — Sir Humphry Davy's address to him on 

 the occasion, 300-302 — on the aberration of compound lenses 

 and object-glasses, 369 — on the separation of iron from 

 other metals, 372 



Hincks, (Rev. Edward) observations of on secret writing, 21 — 

 remarks on Mr. Chenevix's cipher, 22-24, 28 — on Lord 

 Bacon's, 24, 25 — on Mr. Blair's, 25-27 — specimens of 

 ciphers, 29 



Home, (Sir Everard) observations on the rete mucosum of the 

 negro, as a defence against the solar rays, 125, 126 — micro- 

 scopical observations on the brain and nerves, i^c. 127-129 — 

 notice of his account of the Dugong, ^c. 370, and of the 

 peculiarities that distinguish it from the Manatee of the 

 West-Indies, 375 



Humboldt (Baron), observations of on the causes affecting the 

 distribution of vegetable forms, 338, 339 



Hutton (Dr.), notice of his remarks on the mean density of the 

 earth, 370-372 



Hydraulic Lime, analysis of, 414 



Hydrocyanic Acid, salivation and ulceration of the gums pro- 

 duced by, 428 



Hydrogen and Carbon, on the aeriform compounds of, 133, 134 

 — explosion of, and of chlorine, 413 



Hydrophobia, on the use of chlorine in, 190 



Insects (luminous), on the phosphorescence of, 181, 182 

 Iodine, on the combinations of oxides with, 175, 176 — on the 



use of, in medicine, 187-189 

 Iron ore, analysis of granular chromic, 39, 40 — of blue iron ore, 

 38 — alloy.s of iron, chromium, and steel, 173, 174 — on the 

 separation of it, from other metals, 372 — effects of the prox- 

 imity of masses of on the rates of chronometers, 374 — curious 

 effect of sea water on cast-iron, 407 — effect of iron on the 

 rate of chronometers, 415 — oxalate of, found as a mineral, 422 

 Irritation of the spinal nerves, remarks on, 428-430 

 Ivory (Mr.), account of his method of computing the latitude 

 from two altitudes, and the lime intervening, 389, 390 — apo- 



