. The sea [microform] : its stirring story of adventure, peril & heroism. Adventure and adventurers; Voyages and travels; Ocean; Aventures et aventuriers; Voyages; Océan. 804 TIIK SFA. tlu' liittor thai of tlic cmIjj^oh oI" Huctvssivi' "^rowtlis ot" tho slioll. Tlicsc points have tlio inowt aceuruto reBomblunec to thoso Hot on a Htoel ruHj) in a blatkHmith'H wliop. It in interesting to know that tho sholl is prosorvod from lieing itsolf ixM-nianontly worn away ]>y tho fact that it is eoni- jjosed of arra<^unito, a siih- stanco mueh liarder than tliose in whic-h thi' Ph
. The sea [microform] : its stirring story of adventure, peril & heroism. Adventure and adventurers; Voyages and travels; Ocean; Aventures et aventuriers; Voyages; Océan. 804 TIIK SFA. tlu' liittor thai of tlic cmIjj^oh oI" Huctvssivi' "^rowtlis ot" tho slioll. Tlicsc points have tlio inowt aceuruto reBomblunec to thoso Hot on a Htoel ruHj) in a blatkHmith'H wliop. It in interesting to know that tho sholl is prosorvod from lieing itsolf ixM-nianontly worn away ]>y tho fact that it is eoni- jjosed of arra<^unito, a siih- stanco mueh liarder than tliose in whic-h thi' Phohis l)iirrows. Yet we see liy comparini'' spceiineiiK oi\c with nnothcr, that sucii a ileslnietive action (h)eH in time take ])lace, i'or sumo have the raspinj^ points nnieh nioro worn than otiiers, many of tho older ones bcinjj nearly smooth. The animal turns in its liiirrow from side to side when at work, adherinj;- to the in- terior hy the foot, and there- fore only partially rotatiiiy to and fro. The substanee is abraded in the form of lino powder, which is periodieally ejected from the mouth of the hole by the contraction of ilu branchial siphon, a good deal of the more unpal])able portions being deposited by the current as it proceeds, and lodging as a soft mud between the valves and the stone. Mr. Hudson, who watched some Pholades at work in a tide-pool in the chalk, observed the periodic ejection of the cloud of chalk powder, and noticed the heaps of the same material deposited about the mouth of each burrow. The discharges were made with no regularity as to time. Mrs. Merritield records a curious fact :—" A huly watching the operations of some Pholades which were at work in a basin of sea-water, j)erccived that two of them were boring at such au angle that their tunnels would meet. Curious to ascertain wh;it tVicy would do in this case, she continued her observations, and fou jI that f/ie lurfft'r and nfroiiger Fliolns bored strulijhf throvgh the v't-aker one,
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Keywords: ., bookcentury1800, booksubjectocean, booksubjectvoyagesandtravels
