& 
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Bibliography. 175 
light as carbonate of magnesia, which it much resembles ; on lower- 
ing the waters of a small lake this was found under the covering of a 
boggy soil, and in other similar situations. The substance was proved 
to consist almost wholly of the silicious skeletons of infusorial vege- 
tables, if they may be so called, or of those equivocal beings which 
occupy the borders of the two kingdoms, and render it difficult, not 
to say impossible, to draw the line between them. Their discovery 
in England is due to Mr. Binney of Manchester, and we extract the 
following from Mr. Bowman’s account. 
“He [Mr. Binney] informs me that so long ago as 1836, being then 
on a visit in Lincolnshire, he observed a whitish pulverulent substance 
on the sides of a deep ditch, which he at first took to be lime, but on 
examination, finding it to be quite different in its properties from that 
body, he supposed it to be of animal origin. The place where it was 
found is a portion of a reclaimed peat bog, about four feet in thick- 
ness, lying on the upper red marls, one mile east of the escarpment of 
Lias limestone, in the valley of the Trent, in Blyton Car, near Gains- 
borough. The peat was ina high state of decomposition, and had 
been under cultivation for some years. The white substance in ques- 
tion had been thrown out in widening the ditch, and originally occu- 
pied a bed varying in thickness from four to six inches, at the depth 
of about a foot under the surface of the peat, and extending over an 
several acres of land. In some places the powder was mixed 
‘ s of peat; but in others it was quite free from such ad- 
mixttre, When first dug up, it was of a yellowish color, and ina 
State of paste; but on becoming dry it changed to a beautiful white 
powder, that floated in the atmosphere on the slightest agitation, was 
tasteless, and bore a great resemblance to calcined carbonate of mag- 
nesia. Conceiving that it might be fatty matter in a state of adipocire, 
he sa vely treated it with sulphuric, hydrochloric, and nitric acids, 
anda ards submitted it to the action of heat, by all which pro- 
cesses it remained unchanged ; and he was thence led to believe it 
Was silica in an extremely minute state of subdivision. He had sub- 
sequently subjected it, under the action of the blowpipe, to an intense 
white heat for fifleen minutes, and he had treated it with the carbon- 
ates of potash and of soda, and thus formed silicates of these sub- 
stances. He afterwards learned that a similar substance was found in 
considerable abundance near Haxey, in the peat deposit of the neigh- 
boring level of Hatfield Chase, and was informed by the farmers there 
' at wherever it occurred, the soil above it was Very poor and unpro- 
due tive. This fact is a strong confirmation of its being silica, such 
aolls being proverbially sterile. In this stage of his knowledge, Mr. 
ry 
Binney saw Dr. Drummond’s account of the powder from Lough Isl- 
