Derivation of Windfall.—Arvine, in his Cyclopædia, gives the following plausible reason for the origin of this term, now in such common use. Query, Is he correct?

"Some of the nobility of England, by the tenure of their estates, were forbidden felling any trees in the forests upon them, the timber being reserved for the use of the royal navy. Such trees as fell without cutting, were the property of the occupant. A tornado was therefore a perfect god-send, in every sense of the word, to those who had occupancy of extensive forests; and the windfall was sometimes of very great value."

W. W.

Malta.

Do the Sun's Rays put out the Fire?—There is a current and notorious idea, that the admission of the sun-light into a room puts the fire out; and,

after making every deduction for an apparent effect in this matter, I confess I am disposed to think that the notion is not an erroneous one. Can any of your correspondents account for it on philosophical principles, or disprove it experimentally?

C. W. B.

Denmark and Slavery.—Dr. Madden, in A Twelve Months' Residence in the West Indies, 1834, says, in allusion to a remark of Mr. Brydges, to the effect that England was the last European power to enter into the slave trade, and the first to abandon it, "This is inaccurate: to the honour of Denmark be it spoken, the slave trade was abolished by her five years before England performed that act of tardy justice to humanity" (vol. ii. p. 128.). The object of the present communication is neither to question nor disparage the merit here claimed for Denmark, in reference to "the slave trade:" it concerns the abolition of slavery itself by that power. I shall therefore be obliged to any reader of "N. & Q." who will inform me when freedom was granted to the negroes in the Danish island of St. Thomas, in the same manner as to those of the British West Indian colonies in 1838? And also in what work I can find any detailed account of such act of manumission?

L. L.

Spontaneous Combustion.—Is there such a thing as spontaneous combustion?