324 Proceedings of Philosophical Societies. (APRIL, 
and afterwards by Mr. Cavendish, as a means of determining the 
height of places above the sea. Mr. Wollaston’s thermometer is as 
sensible as the common mountain barometer. Every degree of 
Fahrenheit on it occupies an inch in length. The thermometer, 
together with the lamp and vessel for boiling water, wlren packed 
into a case, weighs about a pound and a quarter, and is much more 
portable and convenient than the common mountain barometer. It 
is sufficiently sensible to point out the difference in height between 
the floor and the top of a common table. Mr, Wollaston gave two 
trials with it, compared with the same heights measured by General 
Roy by the barometer. The difference between the two results did 
not exceed two feet. 
On Thursday, March 13, an appendix to Mr. Pond’s paper On 
the Parallax of the Fixed Stars was read. Conjecturing that the 
small difference which occasioned the suspicion of a parallax was 
owing to the difference between the heights of the external and in- 
ternal thermometers in summer and winter, Mr. Pond endeavoured 
to keep the inside of the observatory last winter of the same tem- 
perature as the outside, which the mildness of the season enabled 
him to accomplish. Many observations on « Lyre were made. No 
deviation whatever was observed; or, if any minute deviations 
existed, they were in an opposite direction from that of a parallax. 
At the same meeting, part of a paper by Mr. Marshall on the 
Laurus Cinnamomum, or cinnamon-tree, was read. 
On Thursday, March 20, Mr. Marshall’s paper on the Laurus 
Cinnamomum was continued. He took a review of the descriptions 
of this plant given by preceding botanical writers, and pointed out 
numerous mistakes into which they had all fallen, from not being 
aware of the meaning of the different names given to the plant and 
its varieties by the natives of Ceylon. Linnzus gave to his laurus 
cassia the properties of the laurus cinnamomum ; and Thunberg, 
the last botanist who describes this tree, does not correct the errors 
of his predecessors, and probably was not aware of their existence. 
The cinnamon-tree is cultivated in four different places in Ceylon, 
and it grows wild abundantly in the jungles. The cinnamon ob- 
tained from the cultivated places amounts to rather more than 2000 
bales, and that collected in the jungles is about an equal quantity. 
What is called cassia is the receptacle and unripe seeds of the 
laurus cinnamomum. 
LINN.EAN SOCIETY. 
On Tuesday, March 4, a paper was read, communicated by Dr. 
Leach, from the manuscripts of the late Col. Montague, describing 
a new genus of vermes distinguished by the name of amphiro. Five 
British species were described. They are all inhabitants of the sea, 
distinguished by long tentacule, organs of respiration, and sub- 
stances which answer the purposes of feet. 
At the same meeting, a paper by T. A. Knight, Esq. was read, 
eontaining a vindication of his hypothesis respecting the cause why 
