Grain scales (grain)
The grain scales in use since the 18th century ( grain sampler, bushel scales, grain sampler, grain scales ) were not used to measure certain amounts of grain, but were used to check the quality and residual moisture of grain by measuring the bulk density (i.e. the specific weight of the grain, including the between the grains remaining voids) by weighing a standardized volume.
history
In the Middle Ages, the bulk weight was calculated by measuring, but there were no special scales for this. In 1726 the important encyclopaedist of technical achievements of his time, Jacob Leupold , gave a " description of a grain or grain scale " in his " Schauplatz der Weightkunst und Waagen ". At that time, in the coastal countries of the North and Baltic Seas, “ Dutch grain scales ” were used to determine the bulk weight and thus the grain quality, the principle of which was maintained until well into the second half of the 20th century, at least where grain was by volume and not by volume Weight was traded. Even when the pre-metric dimensions (e.g. “a Dutch sack” of 81.072 liters) went out of use, i.e. the grain scales were no longer used to determine the sack weight, they could continue to be used for quality determination.
In 1844 in Hamburg and in 1846 in Bremen calibrated normal grain scales were purchased for use at the commercial court.
Principle and handling
The grain scale is a proportional scale. Their typical characteristic is a cylindrical metal vessel that forms one of the weighing panes of a beam balance and, when using a skimmer, holds the precise volume of a certain fraction of a standard volume measure for grain. On the counterweight side were weights with corresponding fractions of the pound weight used. Deviations from the target weight could be measured.
literature
- Johann Herrmann Becker: An attempt at a general and special food science, part 1, Stendal, 1811. On pp. 387–388 the literature of the 18th and early 19th centuries on the inventions of proportional scales is listed.
- Measure and weight. Zeitschrift für Metrologie, Special Issue 3: Kornwaagen , 1990, (Reprint of the articles on the topic published in the journal from 1986-2014.) ISSN 0933-4246.
- Jacob Leupold : Theatrum Staticum. The arena of weight art and scales , Leipzig 1726,
- Reinhold Spichal: To each his own - eenem yeden dat syne. Market and measure in history using the example of an old Hanseatic city. Bremen 1990, pp. 251-255.
- N. Schwermann: '' Der Kornprober '', in: Hildesheimer Heimatkalender 1985, pp. 89-93.