Prof. Faraday's Researches in Electricity. 14-7 



The fourth region, formed by the valley of Antioch, is rocky, 

 irregular, and varying from elevations of 220 to 440 feet. It com- 

 prises also the alluvial plain of the Orontes, which gradually sinks 

 to the level of the Mediterranean. This latter district is covered 

 with shrubs, which are chiefly evergreens ; and inhabited by a few 

 families of Syrians, who, in these picturesque solitudes, chiefly fol- 

 low mysterious rites, presenting a mixture of Mahomedanism and 

 Christianity. 



It appears, from the examination of this line of country, that 

 there here exist two distinct regions, the one low and already fur- 

 nished with the means of water transport ; and the other elevated, 

 where the waters, which are lost in the valley of Aleppo, might be 

 turned with facility into an artificial channel. Both regions are re- 

 markably level, and present, when separately viewed, very few difli- 

 culties to be overcome for the construction of artificial roads. 



May 3. — A paper was read, entitled, " Supplementary Note to 

 the Eleventh Series of Experimental Researches in Electricity." 

 By Michael Faraday, Esq., D.C.L., F.R.S., &c.* 



The author describes, in this supplementary note, experiments 

 made with the view of determining the specific inductive capacities 

 of dielectrics, by means of an apparatus of the following form. Three 

 circular brass plates were mounted, side by side, on insulated pillars; 

 the middle one was fixed, but the two outer plates were moveable on 

 slides, so that all three could be brought with their sides almost into 

 contact, or separated to any required distance. Two gold leaves 

 were suspended in a glass jar from insulated wires, connecting each 

 of the leaves respectively with the adjacent outer plate. The amount 

 of disturbance in the electric equilibrium of the outer plates pro- 

 duced by interposing a plate of the dielectric substance to be tried, 

 after charging the middle plate, was taken as a measure of the spe- 

 cific inductive capacity of that dielectric. By varying the size and 

 distances of the plates, and also the distance of the gold leaves from 

 one another, new conditions are supplied for the more exact deter- 

 mination of the relative inductive powers of dielectrics of every de- 

 scription ; and by sufficiently reducing the dimensions of the instru- 

 ment, it may be rendered applicable to comparatively small masses 

 of dielectrics, such as crystals, and even diamonds. An instrument 

 capable of such universal application the author proposes to desig- 

 nate by the name of Differential Inductometer. 



Also read, a Letter addressed to P. M. Roget, M.D., Secretary 

 to the Royal Society, by James Ivory, Esq., F.R.S., accompanying 

 a paper on Astronomical Refractions. Communicated by Dr. Roget. 



The author adverts in this letter to the attempts made by New- 

 ton to solve the problem of atmospherical refractions, which were 

 baffled by the experience that the observed quantities fall far short 

 of the theoretical deductions ; whence he justly inferred that some 

 new cause must be sought for capable of effecting that change in 



* An abstract of Prof. Faraday's Eleventh Series of Researches was 

 given in Lond. and Edinb. Phil. Mag. vol. xii. p. 338. — Edit. 



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