There were only 282 days in the English Calendar in 1751.
The Julian calendar was first implemented by Julius Caesar in 46 B.C. and that had the 25th March as the New Year. This was used by Britain until 1750.
The Gregorian calendar was introduced in 1582 by Pope Gregory XIII and implemented that year in France, Italy, Poland, Portugal and Spain.
When Britain changed to the Gregorian calendar, in 1751, the first year was from 25th March (the day after the end of the Julian calendar year) to 31st December (the last day of the new Gregorian calendar). Hence only 282 days in 1751.
The following year, there was another slight change to get into line with Europe, when from midnight September 2nd 1752, it became September 14th 1752, the next morning. Another smaller year.
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