Page 259 - Third Book of Reading Lessons

258 THIRD BOOK OF
below is equal to the weight of its body, then the re­ action of the air upwards is likewise equal to it; and the bird, being acted upon by two equal rces in contrary directions, will rest between them. If the rce of the stroke is grea r than its weight, the bird will rise with the d erence of these two rces : and if the stroke is less than its weight, then it will sink with the di erence. JoYCE.
LESSON XIX.
THE DIVING-BELL.
2:
CoRK, n., the bark of a tree so called; also pieces of such tree used r stopping bottles, barrels, &c. D. kork, Ger. corck, om (L.) cortex, the bark, om corium, a hide.
SuR1FACE (- s), n., the upper ce, or what rst appears or shows it­ self of anything. F. surface; L. s er cie,s, om super, andfacies, a ce.
CoMPREss'rnLE, a., capable of being pressed close ; yielding to pres• sure, so as that one part is brought nearer to another. F. com­ pressible. See "Expression," p. 15.
ExcLUDE1, v., to shut out; to eject. L. excludo,-ex, and laudo, I shut. CoNDENS1ED, v., thickened; compressed or compacted into a small
space. L. condensatus, om condenso,-con, and denso, I thicken. TRm.'cATED, a., cut, shortened, lopped om the trunk. L. truncatus,
from truncus, cut, maimed.
AN'caoR, n., a heavy iron to hold the ship, by being xed in the
ground; anything that confers stability. F. ancre; I. S. and L. ancora; G. agkura, om ogke (g is sounded like n in both),-a hook, or crook.
Oit11FICE ('-re- s), n., any per ration :-an opening in rm of a mouth. F. or ce; L. or cium, om os, a mouth, and facere, to rm, or make.
VELO</ITY, n., swiftness, rapidity. F. velocite, om velox, L., swift, and this, perhaps, om volo, I y.
CYCLOPE1DIA (sy-), n., a circle of knowledge or instruction in all arts and sciences. F. cyclopedie; L. c. clop dia, om kuklos, G., a cir­ cle, and paideia, instruction, learning.
For "Machine," see p. 241; "Horizon," p. 187 :-and r derivation of" Appended," see Appendage , p. 51.
1. To illustrate the principle of this machine, take