The aim of the work is to closely examine the permeating of Pomeranian coins, struck by the last representatives of the House of Griffins into the Polish monetary market and to determine the scale of the process. The principal research method is the examination of the finds containing Pomeranian coins deposited in Poland, complemented with the analysis of written sources. The exploration of the numismatic material allowed the determination of both the number of Pomeranian coins in Polish deposits (109 certain and 15 probable coins of the last five representatives of the House of Griffins in 49 deposits) and the frequency of individual types of Pomeranian coins (with the absolute prevalence of poltoraks and debased groschen). It also helped to arrive at the conclusion as to the direction of the influx of the Pomeranian coins into Poland (while in the second decade or the first half of the third decade of the 17th century the Silesian route may have been prevalent, from the third decade of the 17th century the northern direction seems to have been more probable). The analysis of political and economic relationships made it possible to explain the absence of Pomeranian coins in hoards from the Poland-Brandenburg borderland and the area at the border between Greater Poland and the Duchy of Pomerania.
In this paper the influence of high power airborne ultrasound on drying biological material (Lobo apple) properties is considered. Apple samples were dried convectively at 75 ◦C and air flow of 2 m/s with and without ultrasound assist at 200W. During experiments, sun-drenched and not sun-drenched part of fruits were considered separately to show, how the maturity of the product influences dry material properties. Dried apple crisps in a size of small bars were subjected to compression tests during which acoustic emission (AE) was used. Analysis of AE and strength test results shows that correlations between received acoustic signals and sensory attributes (crispness, brittleness) of dried apples can be found. It was noted that ultrasound improved fruit brittleness in comparison with pure convective processes, where fruit maturity determines a kind of destruction and behaviour of dried apple crisps.