The Geographical Journal (Journal of the Royal Geographical Society): Volume XII, No. 2 [‎299r] (100/154)

THE MONTHLY RECORD.
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Damian in 1887 (cf. Journal, vol. i. p. 351), while other measurements show a
similar decrease. This is due to the fact that the loss by the subterranean outlet
(the lake lying in a Karst region) more than balances the supply of water by
streams. It has been proved by the use of fluorescent liquids that the Ischia
Podetti, a small stream which empties itself into the Adige, derives its water from
a subterranean outlet of the lake. The results of soundings Measurements of the depth of a body of water. , temperature determina
tions, etc., are also given by Battisti with regard to the small lakes of the lersina
district, the most noteworthy point being the phenomenon observed in the Lago
delle Valle di Fornace and the Lago Santo, of warmer water in the lower layers
than at the surface, in spite of the fact that the lakes were frozen over. Battisti’s
explanation that this is due to hot springs can hardly, Dr. Halbfass thinks, hold
good of the former lakes, where the warmer zone takes up the greater part of the
lake.
Increase of the Po Delta during the Nineteenth Century— Prof.
Marinelli discusses the question of the progressive increase of the area of the Po
delta in the Revista Geografica Italiana (1898, Nos. 1-3). Having, by a com
parison of the Austrian map of about 1823 with the result of modern surveys
carried out in 1893, arrived at the conclusion that the mean annual increase
during those seventy years has been about '762 sq. kilom. ('293 sq. miles% the
author compares this result with those obtained earlier in the century by De Prony
and Lombardini, the only observers who had previously studied the question in
detail. This comparison leads at first sight to the conclusion that the rate of
increase has varied greatly within the period for which data are available, Lom-
bardini’s estimate for the interval 1600-1830 having given an annual increase
of no less than 1'35 sq. kilom. ('518 sq. miles). Of the causes which might be
appealed to as an explanation of such variation, Prof. Marinelli rejects those con
nected with changes in the amount of rainfall, deforestation, etc. He is more inclined
to give weight to such factors as the increased depth of the sea, and its more
powerful degrading influence in proportion to the advance of the coast-line, or a
possible subsidence, owing to the effects of sedimentation. But an examination
of the data on which the estimates respecting the earlier periods are based, shows
that no implicit reliance can be placed on these, for a very slignt displacement o
the position assigned to the coast at an early epoch would materially altei t ic
proportionate increase before and after such date. Taking the mean of the rates
of increase given by Lombardini for the periods before and after 1599, a result is
obtained which differs but little from that arrived at by Marinelli for the present
century, the slight decrease observable in the latter being easily accounted for by
the causes above alluded to. The estimated total increase during six centuries
amounts to 516 sq. kilom. (198 sq. miles), which means that, by the action of one
river alone, Italy has in that period gained no less than of its previous area,
while recent surveys show that the increase is actively maintained at the present
day. At the end of his article, Prof. Marinelli gives some notes on the length of
time which would probably be required to fill up the whole of the Northern
Adriatic above 44° 45' N. lat. The disposition now displayed by the mouths of
the Po to bend in the direction of the axis of the gulf introduces a special element
of uncertainty, but the writer The lowest of the four classes into which East India Company civil servants were divided. A Writer’s duties originally consisted mostly of copying documents and book-keeping. considers that the time required would certainly
exceed 100 centuries, and would probably be more than 120.
ASIA.
Journey in Northern Su-chuan.—A recently issued Consular Report, by
Mr. G. J. L. Litton (Miscellaneous Series, No. 457), is of special value, as contain
ing the account of a journey through some of the least-known parts of Northern