Determination of the day of the week possible to do all the calculations in one's head with a little practice). None of the methods given here perform range checks, so unreasonable dates will produce erroneous results. Every seventh day in a month has the same name as the previous: "Corresponding months" are those months within the calendar year that start on the same day of the week. For example, September and December correspond, because September 1 falls on the same day as December 1. Months can only correspond if the number of days between their first days is divisible by 7, or in other words, if their
Mines on the first day of the Somme Mines on the first day of the Somme The 19 mines on the first day of the Somme comprised a series of underground explosive charges, secretly planted by British tunnelling units beneath the German front lines on the Western Front during the First World War, ready to be detonated in the morning of Saturday 1 July 1916, the first day of the Battle of the Somme (1 July – 18 November 1916). The joint explosion of these mines ranks among the largest artificial non-nuclear explosions. The tunnelling companies of the Royal Engineers were to make two major contributions to the