Sleep in a 1-year diary from the mid-18th century.

A 1-year systematic diary was kept by an anonymous diarist in Hamburg in the year 1755-1756. Sleep, activities, food intake, urine volume, and meteorological data were documented daily. The systematic recording of sleep and naps, with an accuracy of a quarter of an hour allowed analysis of the placement, duration, and consistency of sleep. The mean (range) night sleep duration was 6 (3-9) h. The distribution of sleep interruptions showed two peaks, short (≤30 min) and long (≥45 min) interruptions. The latter indicted nights with segmented sleep. Time in bed was subject to strong seasonal variations. Bedtime and rise time were earlier in summer than in winter and sleep latency was shorter in summer than in winter. However, sleep duration displayed a large spread in all seasons and did not differ substantially between summer and winter. Seasonal variations of sleep timing were related to the varying daylight hours during the year. Finally, the results of this individual case may prompt a more detailed investigation of the variability of sleep behaviour in the pre-industrial period.

["Whether the Lord putted Moscow and neighbouring cities empty?": Moscow pest of 1654].

The first ten years of the reign of Tsar Alexei Mikhailovich were distinguished by extreme turbulence. The unsuccessful actions of the "government" of the boyar Morozov provoked chain of city riots which reached their apogee in famous "Salt Riot" in the capital. After that, religious feuding began that in near future resulted in the Schism. Afterwards, Russia, after long hesitation, entered the war with the Polish-Lithuanian Commonwealth that as it turned out, prolonged 13 years. Finally, in 1654, after long break, the plague again visited Russia. The plague pestilence of 1654-1655 was relatively transient (it began in summer and gradually faded away with the onset of winter), however very deadly and shook both the Russian state and Russian society to the ground. It disrupted habitual regular way of life and unsettled all and everything. The authors propose original version of origin of this epidemic and reconstruct its course and consequences on the basis of evidence of contemporaries and extant documents.