. Science-gossip . refamiliarly known to us as Chalk. Indeed, a promi-nent member of the Challenger expeditionannounced, whilst the novel results found werescarcely thoroughly examined, that we were stillliving in the cretaceous epoch. This statement is,however, now completely scouted by scientific men ;but it was peifectly excusable in the early excitementaroused. Deposits were found, some consistingprincipally of microscopic calcareous (chalky) for-aminifera or pteropoda, others principally composedof silicious (flinty) microscopic organisms belonging tothe order Radiolaria, or to the vegeta
. Science-gossip . refamiliarly known to us as Chalk. Indeed, a promi-nent member of the Challenger expeditionannounced, whilst the novel results found werescarcely thoroughly examined, that we were stillliving in the cretaceous epoch. This statement is,however, now completely scouted by scientific men ;but it was peifectly excusable in the early excitementaroused. Deposits were found, some consistingprincipally of microscopic calcareous (chalky) for-aminifera or pteropoda, others principally composedof silicious (flinty) microscopic organisms belonging tothe order Radiolaria, or to the vegetable oozes are pelagic, that is, occur far from land. It is estimated that for about 200 miles out atsea, all around our continental coasts, the bottomof the sea is covered by what have been classed asShore Deposits. These result from the gradualdenudation of the land, and consist of great accumu-lations of river and coast detritus. The clay or mudbrought down by rivers is carried far out to sea in. Sponge Spiclles. a state of fine sub-division. It is deposited beyondthe influence of tides and currents. Sand similarlycarried down by the rivers to the sea, in a state ofsuspension, isby reason of its heavier nature, depositedwithin this 200-niile limit earlier than the clay, so thatin this area we have sedimentary rocks will constitute the clays, the chalks, and thesands as true geological formations in ages to come. Beyond this limit, we arrive at a point out of reach ofthe influences of rivers and tides, and difti^rent condi-tions prevail. Roughly speaking, after we pass beyondthis imaginary boundary, and reach those parts wherethe depth of the ocean varies from one to two andhalf miles, we come, both in temperate and tropicalregions, to those areas whece the great calcareous SCIENCn-GOSS// ; iis arc fiirinirig. These have received the nameof Oozes. Accordirn; to the predominalinf; , these oozes are known as Oozeor
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