406 Scientific Intelligence . 
winter of 1819-20, when the thermometer during night was 
from 15° to 17° below 0° of Fahr., and during the day, from 
10° to 12° below it. The reports of the rending ice were 
like that of a six-pounder, and the openings were from 10 to 
15 feet wide. — See American Journal of Science, vol. ii. No. 1. 
p. 177. 
' v ’ 
23. New Volcano near Leiria, in Portugal . — It is stated in 
the Gentleman’s Magazine for April, that a volcano has burst out 
on the highest summit of a ridge of mountains, near Leiria, in 
Portugal. It occurred at the period of the high rise of the 
Douro, and was in full eruption when the latest accounts were 
dispatched. 
24. Eruption of a Spring near Ripon. — On the 18th of April 
1821, a portion of the avenue of Mr Charnock, at Bishop 
Moncktown, near Ripon, was seen in a considerable state of 
agitation for some minutes. An opening, of about a foot 
square, then appeared, and from this there issued a body of wa- 
ter, which ebbed and flowed during the day. The cavity was 
gradually enlarged, by the successive eruptions of the spring, 
and, when plumbed in the evening, was found to be 58 feet 
deep. — Gentleman's Magazine , May 1821, p. 461. 
25. Tree which produces the Caoutchouc , or Elastic Gum . — 
In the region of the Missisippi, on the Arkansas and Red River, 
grows the tree which yields the vegetable caoutchouc. It has a 
tolerably smooth back ; and when incisions are made in it, a 
milky fluid exudes, which coagulates, and forms elastic gum. 
Some trees yield from 150 to 200 pounds of caoutchouc. Mr 
Bringier observed, that the wood of it was very elastic, when 
dry. If rubbed on a body which is electric, particularly in a 
cold day, the body rubbed will adhere to the wall. A quill, 
for example, will be attracted six inches from the wall, and 
stick fast to it, till all the electricity is dissipated. 
26. Account of the Leech of Ceylon. —This animal is seldom 
more than half an inch long, and is nearly semitransparent 
It is very active, and is said occasionally to spring. Its powers 
of contraction and extension are very great. It is like a fine 
cord when fully extended, and its point is so sharp that it 
easily makes its way through very small openings. It is sup- 
