Hoyal Society of Edinhnrgh.— Society of Leghorn, \47 



ROYAL SOCIETY OF EDINBURGH. 



Since our last Report different interesting communications have 

 been made to the Society by the indefatigable Dr. Brewster, " On 

 the phpenomena of optical contact ; the inflexion of light ; the 

 colours of thin plates ; the production of nebulous images by 

 doubly refracting crystals ; the distribution of the polarising 

 force in tubes, cylinders, and plates of glass ; and the effects of 

 mechanical pressure in communicating double refraction to re- 

 gularly crystallized bodies ; also a very extensive series of ex- 

 periments on the action of regularly crystallized bodies upon 

 light." 



A paper by the Rev. Dr. Fleming, " On the junction of the 

 fresh-water of rivers with the salt-water of the sea," details a 

 number of experiments made in the Firth of Tay, with an ap- 

 paratus by which water could be brought from any given depth. 

 It appears from these experiments, that when the flow of a river 

 is obstructed by the tide, the salt-water slides under the fresh like 

 a wedge, and sends the fresh to the surface. 



Dr. Henry Dewar exhibited some words formed in relief for 

 the use of the blind and deaf lad Mitchell, in whose instruction 

 the Society has taken a laudable interest. 



A letter from Professor Playfair presented " An account of some 

 appearances on the sides of the mountains in Switzerland, consi- 

 dered by the writer as analogous to the parallel roads of Glenroy in 

 Scotland." They consist of Hues extending nearly horizontally 

 for miles, and on inquiry were found to have been formed for the 

 purpose of irrigation ; whence it is inferred that those of Glenroy 

 may have had a similar origin. 



Mr. Bald, civil engineer, communicated " Experiments made 

 with Sir H. Davy's safety-lamp in mines in Ayrshire." The re- 

 sults agree perfectly with those made in other mines, and already 

 laid before our readers. 



A communication by Mr. Bonar presented " Observations on 

 the filiation of the various languages of the eastern part of 

 India, and on their affinity witlv the Sanscrit and the Chinese." 



SOCIKTY OF LEGHORN. 



An Academyof Sciences, Lettersand Arts has justbeen establish- 

 ed at Leghorn. It held its first sitting in the Hall of the Palace of 

 Pullie, and was attended by all the public functionaries,nianystrati- 

 gers of distinction, and several of the professors of Pisa. Agreeably 

 to the desire of His Highness the Grand Duke, who has honoured 

 the Society with his patronage, it is every fnonth to publish the 

 K 2 best 



