INDEX. 65 



Dichroism of tourmaline, remarkable, xiii. 219 



Dick (M. T. L.), observations of, on the appearances called the 

 parallel roads of Glenroy, iii. 132 



on those of Lochaber, v. 175 



Dictionary of Chemical Apparatus, Review of, xviii. 832 



Diet of valetudinarians, remarks on, xiv. 367 



Differential Thermometer described, viii. 218 



DiGBY (Sir Kenelm), notice of the pretended alchemical re- 

 searches of, ix. 235 

 Digestion, influence of the eighth pair of nerves on, illustrated 

 by experiments and remarks, x. 292 



— of ruminating animals, experiments on, xix. 169 



Digestive organs, the action of, explained, iii. 305 



— — canals in the foetus of vertebral animals, observations 



on the contents of, xx. 197 

 Digitaline, process for obtaining, xviii. 178 

 Dilatation of fluids, observations on, ii. 163 



DiLLWYN (L. W., Esq.), observation of, on fossil shells, xvii. 129 

 Diod-griafol, notice of a liquor so called, xi. 394 

 Dip of tlie needle, observations on, x. 459 



Dip micrometer and dip sector, observations on the use of, v. 223 

 Dipping-needle, directions forusing, v. 21 1 



■ invention and uses of, vi. 84, Table, and 



causes of its variation, 89 



■ . general results of, xvii. 104. Experiments 



and observations on the daily variation of the horizontal and 

 dipping needles under a reduced directive power, xvii. 128 



Disney (John, Esq.), conjectures of, concerning the original for- 

 mation of the Arabic digits, i. 166 



Dissemination of plants, observations on, iv. 1 



Distance, on the origin of our notion of, iii. 1. Outline of 

 Bishop Berkeley's theory, 2. Notions of distance and magni- 

 tude, how far acquired by the sense of touch, 3. Proof 

 that perception and idea are homogeneous, 6 



Distension, simple mechanical, the cause of the action of invo- 

 luntary organs of sensation, ii. 22 

 ♦ F 



