314 Scientific Intelligence. [Aprit, 
were all, except the last, furnished me by the kindness of Sir 
George Staunton. The last is precisely of the same nature as 
the sceptre sent to his Royal Highness the Prince Regent, and 
was put into my possession for the purpose of examiation by 
the Hon. Mr. Amherst, to whontit was presented by one of our 
attendant Mandarins.” 
The only part of this description which cannot be reconciled 
to prehnite is the infusibility before the blow-pipe. The specific 
gravity of the fibrous variety of prehnite is 2-901, its hardness is 
nearly the same as that of the Yu; and though its fracture is 
always fibrous, yet I can conceive it to be described by a person 
not familiar with the external characters, as having a splintery 
fracture, which is not altogether erroneous. The infusibility 
before the blow-pipe seems to separate the Yu both from preh- 
nite and from nephrite to which Mr. Abel refers it. 
IX. Temperature of the Bottom of the Sea. 
The following are all the observations on this interesting sub- 
ject which Mr. Clarke Abel preserved. The rest were lost by 
the unfortunate shipwreck of the Alceste. The observations in 
the following table were made in the Yellow Sea. 
S Tempera- [Difference of 
North [East ton es : ture ofseaat|temp, between 
3 : “| Current. |'= € | Air : 
latitude. gitude. 2s Gut Bot lAseand poe a 
pe face. | tom, surface.) tom, 
July 23. 8a,m.j35°  1’/123° 46’\11 miles. | 40 |76°| 74° | 65° g° 9° 
24,12m. |36 24 {122 59 —_ 15 (75 | TI 67 4 4 
25. 8a.m./3T 30 |122 40 — 20 \72 | 67 | 62 5 5 
—. 8p.mj— —|— — _— 15 \74 | 69 | 66 5 3 
26. 6a.m.|37 58 |12l 34 _ 15 |\74 | 67 66 T 1 
27.11 p.m.|38 12 120 20 | T miles.| 15 |75 | 74 | 72 ] 2 
(Ibid. p. 67.) 
Mr. Abel states an experiment on this subject by Captain 
Wauchope of his Majesty’s ship the Eurydice, which deserves 
to be stated here as one of the most striking and instructive 
upon record. Within a few degrees of the equator during a calm, 
Capt. Wauchope put his apparatus overboard, and allowed it to_ 
descend till it had carried out 1400 fathoms of line. But he 
estimated the perpendicular depth at 1000 fathoms. The tem- 
perature of the surface was at 73°. On drawing up the instru- 
ment, he found the inclosed thermometer marking 42°—a 
difference of temperature between the surface and given depth 
of 31°.—(Ibid. p. 347.) 
X. Ulmin from a Cork Tree. 
This substance was collected by Dr. Leach from a decayed 
cork tree on the estate of Marriott, Esq. of Wimbledon. 
