1894 - 95 .] Dr R. Munro on Lake-dwelling Research. 
391 
to light in the course of agricultural operations. Such works are, 
however, usually confined to small lakes and hogs. The idea of 
partially lowering the surface of the extensive sheets of water in 
the Jura valley, comprising the Lakes of Bienne, Neuchatel, and 
Morat, was too chimerical to be ever entertained by archaeologists. 
But what was inconceivable and utterly beyond hope from this 
point of view became, in the interests of agriculture, not only a 
practical problem, but is now an accomplished fact. Between 
these three lakes there stretches a vast mossy district, known as 
the “ Gross Moos,” through which the combined surplus water of 
the two latter finds its way to the former. This surplus water 
again emerges from Lake Bienne and is carried off by the Lower 
Thielle which, before the “ Correction des Eaux du Jura^^ united with 
the Aar a few miles down the valley. As the surface of these 
three lakes is nearly on the same level, it is more than probable 
that, in pre-historic times, their waters formed one united sheet 
which, in the course of time, became separated into three lakes by 
the interposition of the sedimentary and peaty deposits now form- 
ing the “ Gross Moos.” Their connecting channels, the Broye and 
the Upper Thielle, owing to the sluggishness of the flow, became 
gradually raised by the constant deposition of mud — thus pro- 
portionately raising the level of the confined waters, and render- 
ing the surrounding lands more and more liable to submergence. 
Also, the river Aar, though passing quite in the vicinity of Lake 
Bienne, went a long way beyond it, and often caused great havoc 
by flooding the richly cultivated lands which it traversed until it 
joined the Lower Thielle. 
To remedy these defects the Swiss Government entered on the 
gigantic project of deepening the entire waterway, from the junction 
of the Lower Thielle with the Aar to the outlet of the Broye, in 
Lake Morat. The scheme also included the cutting of a new 
channel for the Aar, by means of which it would be entirely 
diverted from a considerable extent of its old course and made to 
debouch into Lake Bienne by a straight and much shorter route. 
The hydrographical effect of these works, begun in 1868 and only 
completed a few years ago, was to lower the surface of the lakes 
from 6 to 8 feet. 
In the winter of 1871-72, these operations began to tell on Lake 
