234 Wernerian Natural History Society. 
a former paper Mr. K. had proved that gravitation was the 
chief cause of the descent of the roots of plants; in the 
present he meant to illustrate, by an account of his experi- 
ments, how certain plants extend their roots towards water, 
and others in a-direction from water, without any thing of 
sensation or animal sensibility, as erroneously supposed by 
some vegetable physiologists. His experiments established ~ 
this position sufficiently on mechanical principles, in con- 
sequence of the natural inclination to, or aversion from, 
humidity, according to the particular nature of the plant. 
He also proved that carrots and parsnips sown in a poor 
gravelly soil, under which was placed a rich loam, passed 
through the former, and extended their radicles into the 
rich loam eighteen inches below the surface. 
March 14.—A long and learned paper, by Mr. Baily, 
was read, on the eclipse of the sun predicted by Thales, as 
recorded by Herodotus. The author entered minutely into 
the historical and chronological data which support his 
opinion, and concluded that the eclipse alluded to was an 
annular one, which occurred in the year 610 before Christ. 
WERNERIAN NATURAL HISTORY SOCIETY. 
At the meeting of the Wernerian Natural History So- 
ciety at Edinburgh, on the 12th of January last, Professor 
Jameson read the first part of a series of observations on 
the geognostic relations of the rocks of the island of Arran. 
In this memoir he described particularly the granite, gneiss, 
mica-slate, and clay-slate formations, and also the red 
sandstone, and porphyry-slate, which occur so abundantly 
in that island. When describing the granite, he stated as 
a conjecture, that quartz might prove to be an older forma- 
tion than granite, because the oldest granite contains much 
quartz, but little mica; and.less felspar than the newer va- 
nieties. He pointed out several observations to be made 
with the view of verifying or refuting this conjecture. 
In his description of gneiss he alluded to the veins of gra- 
nitic gneiss which traverse it, and which, when the gneiss 
and granite are in contact, have been represented as veins 
of granite shooting from the subjacent into the superin- 
cumbent rocks. The red sandstone the professor appeared 
inclined to refer to the first or old red sandstone of 
Werner. When describing its stratification and structure 
hepointed out the’ appearances that ought to be attended 
to, in endeavouring to ascertain the dip and direction of the 
strata, and cautioned observers against confounding the 
structure of individual beds with the direction and dip om 
the 
