Tam o' shanter (cap)

A tam o' shanter (in the British military often abbreviated to TOS) is a name given to the traditional Scottish bonnet worn by men. The name derives from Tam o' Shanter, the eponymous hero of the 1790 Robert Burns poem.

The tam o' shanter is a flat bonnet, originally made of wool hand-knitted in one piece, stretched on a wooden disc to give the distinctive flat shape, and subsequently felted. The earliest forms of these caps, known as a blue bonnet from their typical colour, were made by bonnet-makers in Scotland. By the year 1599 five bonnet-makers guilds had formed in cities around the country: Edinburgh, Aberdeen, Perth, Stirling and Glasgow. At the end of sixteenth century, it was said that the Scottish caps were the normal fashion of men and servants, and they remained so throughout the seventeenth century.

Similar in outline to the various types of flat bonnet common in northwestern Europe during the 16th century, the later tam o' shanter is distinguished by the woollen ball or toorie decorating the centre of the crown; the name itself did not enter common usage until the early 19th century, subsequent to the popularity of Burns' poem. The term came to denote a hat, usually associated with Scottish military regiments, derived from the old bonnet, along with the Glengarry and the Balmoral bonnets. The Balmoral was sometimes simply described as synonomous with the tam o' shanter.

Before the introduction of inexpensive chemical dyes in the mid-19th century, the Scottish knitted bonnet was made only in colours easily available from natural dyes, particularly woad or indigo (hence "blue bonnet"). Since that time the tam o' shanter has been produced in a wider range of fabrics, such as serge, as single colours, as well as tartan. Women have also adopted a form of this hat, known as a “tammy” or “tam”.

In the First World War, a khaki Balmoral bonnet was introduced in 1915 for wear in the trenches by Scottish infantry serving on the Western Front. This came to be known as the 'bonnet, tam o' shanter', later abbreviated among military personnel to 'ToS'. It replaced the Glengarry – which was the regulation bonnet worn by Scottish troops with khaki field dress at the start of the war. Originally knitted, the military tam o' shanter subsequently came to be constructed from separate pieces of khaki serge cloth.

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