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Other branches of building-material industry, as concrete- and glass-industries, are also exploiting raw materials from beds in situ, for instance sands and gravels of river, sanders and dune origin.

b) Deep cuts of river and glacial meltwater-river valleys into the surface of the earth, enable us to reach the unveiled layers of the Tertiary-age and facilitate the exploitation of Oligooene glauconie sand, Miocene brown coal and Pliocene, so called ‘speckled’ or Poznań loam.

2.    Landforms produced by vegetation comprehend peat-bogs situated on flood and outwash plains, as well as in dead- and inland-ice depressions (so called eye-holes). Great peat areas are used as meadows and pasture-ground or are exploited for fuel purposes.

3.    Minerał structure of the outer earth-layers is of a great significance for many practical reasons. Deep and heavy foundations of buildings, permeability of water and pressure-endurance of ground — all these pro-blems can influence decisions, concerning realization of aerodromes, canals, dwelling settlements etc.

III.    The soils of the Polish Lowland are mostly genetically bound with glacial and postglacial depositional activity. On the moraine plateau of Ziemia Chełmińska (Chełmno-Land), for instance, fertile clayey soils have developed. On the other hand, barren, sandy soils characterize the dune Basin of Toruń, as well as the sander outwash plain of Bory Tucholskie (Tuchola-Forest). Fertile river-loames appear in the Lower Vistu-la Valley, below Chełmno. On the peat plains of Western Kujawy — dried up bottoms of former lakes — very fertile black humus soils have devel-oped in recent time.

The knowledge of main geomorphological types of soils enables us — in case of lack of a detailed, special map of soils — to put forward preliminary suggestions concerning the regionalization of agricul-ture, localization of anti-wind forest belts, afforestation of barren lands and so on.

IV.    The usefulness of the Geomorphological Map of the Polish Lowland for regional planning and economical analysis of location values — does not exhaust all advantages of this map. The so called urban phy-siography is also based on discussed materiał. The scalę of map illustration of mentioned physiography oscillates between 1 : 2,000 and 1 :10,000. Urban physiography is of great significance, especially for sol-ving difficult problems connected with detailed location of important objects of investment in great cities.

I should like to finish my short report with two following conclusions:

1)    A complete cover of our region by means of geomorphological maps is necessary as soon as possible,

2)    Other elements of geographical enviroment, such as climate, waters and soils — should be also mapped, in a manner serviceable for regional planning.

The maps mentioned above should become not only a permanent instrument in hands of a regional planist, but also a bridge linking both parts of geography, as well as all natural science with economy and sociology.