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
The First Day on the Somme The First Day on the Somme The First Day on the Somme () is a First World War military history book by Martin Middlebrook, first published in 1971 and still in print, which is regarded as a seminal work in the field of World War I scholarship reflecting England's perspective in the conflict. Its text covers in detail the events leading up to and during 1 July 1916, the first day of the Battle of the Somme, concentrating almost exclusively on the British Army's experiences and focussing only in relief on French Army's contribution, especially south of the Somme River.