SCIENTIFIC SUMMARY. 
417 
maximum rate of deposition has also been used, as giving the minimum of 
time. He considers that the geological evidence shows that as the silting 
went on, and the area became converted into land, peat grew, and gradually- 
spread over the newly-formed ground. But, in process of time, the climate 
became unsuited for the growth of peat, which gradually lost its vigour, and 
finally ceased to form. Hence a wide stretch of silt-land borders the Wash, 
upon the surface of which no peat has ever formed. The peat died upon its 
eastward march ; the silt still travels on. The nearest approach of the peat 
to the banks along the line of most rapid accumulation, is twelve miles dis- 
tant therefrom. The age of this, the newest peat in the Fenland, the author 
thinks can be thus determined. Between the “ Homan ” banks and the sea 
lie four miles of silt, which has taken 1,700 years to accumulate. Between 
these banks and the peat lie twelve miles of silt, which, at the same rate of 
formation, would take 5,100 years to accumulate. Adding 5,100 to 1,700 
years, the author finds 6,800 years as the least possible age of the newest 
peat. This peat has yielded many neolithic implements; hence we may 
assume that 7,000 years will take us back into the neolithic age. The 
author remarks upon the coincidence of this estimate with two Swiss ones 
previously referred to, but observes that these results do not give us the 
date of the introduction of neoliths into Europe, for neither in the Swiss 
nor English localities are we sure that the neolithic relics belong to the 
early part of the neolithic age. The author further states that he has re- 
cently obtained evidence of neolithic handiwork in Fenland peat of far 
greater age than that described ; the peat-bed underlying silt more than 7,000 
years old. He is inclined to think that the neolithic age in England began 
at least 10,000 years ago — and perhaps 20,000 years ; but that it does not 
approach the close of the glacial epoch, he thinks is shown by the fact that 
the older Fenland beds (themselves in part glacial) do not contain human 
relics. 
ASTRONOMY. 
Biela's Comet . — It is well known that when this comet returned to peri- 
helion in 1866 and again in 1872, the heavens were searched in vain for it, 
by many of the most careful and trustworthy observers. It seems exceed- 
ingly unlikely that telescopists will meet with greater success this year. 
Calculation seems set completely at defiance. In the first place it is to be 
remembered that every return of this comet increased the accuracy with 
which its orbital motions were known. So that as it had been at once iden- 
tified in 1846 and again in 1852, astronomers had every reason to expect 
that it would be much more easily found in 1866 (in 1859 its geometric 
path brought it too near the sun’s place in the heavens for a successful search 
to be instituted). In 1872 the chance of finding it had only so far dimi- 
nished, that the failure of astronomers showed that something hadjgone 
wrong. There was good reason to believe that the failure to recognize the 
comet did not in any way arise from unknown perturbations to which the 
comet had been subjected, but from a further disintegration of the comet’s sub- 
stance, already so far effected that since 1846 this object had in reality become 
NEW SERIES, YOL. III. — NO. XII. E E 
