222 
S clentific Intelligence*— Botany .—A rts. 
BOTANY. 
22, Luminous Plants. — It is well known that some plants are 
luminous; and also that parts of plants in an incipient state of de- 
composition, shine more or less. The following instances of this 
property are given at present ; it being our intention, in a future 
number of the Journal, to enter fully on this subject. 1. Po- 
tatoes, kept in cellars, in a growing state, and therefore useless 
as food, sometimes become so luminous, that we can read by 
them the print of a book in the dark. 2. The Dictamnus al- 
bus spreads around it, in dry summer evenings, an atmosphere 
which, on the approach of a taper, inflames with a bright blue 
flame. 3. Other plants give out a sparkling light , probably of 
an electrical nature ; such is the case with the flowers of Calen- 
dula, Tropaeolum, Lilium bulbiferum and chalcedonicum, Ta- 
getes, Helianthus, and Polyanthes, as mentioned by Mr John- 
son of Wetherby in Vol. iii. p. 415. of this Journal. 4. Some 
plants give out a calm steady light, of a bluish, greenish, or 
yellowish-white colour, such as Dematium violaceum, Pers . ; 
Schistostega osmundacea, W. and M. ; Phytolacca decandra, 
Hhizomorpha pinnata, Hurnb ., & c. The luminous appearances 
in the galleries and shafts of our mines are often to be traced to 
rhizomorphous plants. 5. The milky juice of some plants is very 
luminous. 6. Trunks, branches, and roots of trees, in an inci- 
pient state of decomposition, become luminous. 
ARTS. 
23. Extraordinary extent of the Baize and Flannel Manufac- 
ture at Rochdale. — 44 In the town of Rochdale, and the adjacent 
villages, there are manufactured, every week, of flannels and 
baizes, about 20,000 pieces, of 46 yards each, making 
47,840,000 yards per annum. It is supposed that 17,840,000 
yards are exported ; the remaining 30 millions of yards are con- 
sumed in the United Kingdom, being an average of about 1| 
yards for each individual. Some good flannels are manufactur- 
ed in Wales; a few coarse ones at Keswick, and some other 
towns and villages in the kingdom. A few are manufactured 
on the Continent, and works for that purpose are now erecting 
in America ; but the whole of the flannels manufactured on the 
globe, besides those manufactured in Rochdale and its imme- 
diate vicinity, are not equal in quantity to those made there. 
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