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A haversack or small pack is a bag with a single shoulder strap. Although similar to a backpack, the single shoulder strap differentiates this type from other backpacks. There are exceptions to this general rule.
The name 'Haversack' originates from its usage to carry 'Havercake' and almost certainly related to Hafer, the German word for Oats. Havercake was a rough type of bread simply made from oats and water, with the addition sometimes of yeast to bulk it out. Oats were the staple food of the poor, especially in the textile districts of the north of England, during the privations caused by the Napoleonic Wars. Havercake was made in the form of a thick biscuit as a convenient way to take food to the factory for the mid-day meal, and the haversack was the bag it was carried in. This system, using havercake carried in a haversack, was also used widely by the military for the individual soldier to carry his rations. The Duke of Wellington's Regiment was nicknamed the 'Havercake Lads' because the recruiting sergeants used to display a piece of havercake held aloft on a bayonet, to signify that food would never be a problem if enlisted; a great encouragement to recruiting when the general population was starving.
The haversack, especially when used in the military, was generally about 30 cm by 30 cm with a button-down flap to close it. When empty the bag could be folded in three and an extra button on the back of the bag would allow it to be refixed in this position. For the military this made it neat and, when held to the side in its folded form by the soldiers belt, it became part of the uniform of many regiments in the British army.
In Australia and elsewhere, the word haversack is synonymous with rucksack or other similar terms and is used to describe any backpack.
U.S. ARMY HAVERSACK
Haversacks were in use during the American Civil War, as recounted in Grant's memoirs, "In addition to the supplies transported by boat, the men were to carry forty rounds of ammunition in the cartridge-boxes and four days' rations in haversacks."
In 1910 the U.S. Army adopted the M-1910 haversack (or M10) as the standard back pack for all infantrymen. The pack is essentially a sheet of rugged khaki-coloured canvas that folds around its contents (bedroll, clothing, daily rations, and assorted personal items), and is held together by flaps and adjustable buckle-straps. The two shoulder straps are designed to attach to a web belt or suspender configuration. The exterior of the pack has loops, rings, and grommet tabs for attaching a bayonet sheath, a "meat can" (mess kit) pouch, and a canvas carrier for a short-handled shovel (a.k.a. entrenchment tool).
This pack remained in service, most notably during World War I, until 1928 when it was superseded by the slightly modified M-1928 pack. However, thousands of surplus M10s were issued during World War II to compensate for shortages in war-time textile production.
The M-1928 haversack (M28) continued to be the standard-issue army back pack for the duration of World War II. The only exceptions being officers, engineers, paratroops, and medics who were issued the more compact M-1936 Musette Bag. The M28 was gradually phased out starting in 1944 with the introduction of the olive drab M-1944 and M-1945 Canvas Combat Field Pack configuration. This new two-part design, based on the Marine M-1941 system, used a much smaller back pack (for rations, clothes, ammunition, and messkit), and a separate Cargo Bag that attached to the bottom for extra clothes, shoes, and misc. items. The upper field pack had the same type of grommet tabs and loops as the M-1928 for attaching a bayonet and entrenchment tool plus straps for securing a "horseshoe" bedroll.
U.S. MARINE CORPS HAVERSACK
The marines carried the M10 and M28 haversack in both world wars, but they also developed their own exclusive pack system in 1941. The M28 was considered cumbersome and unsuitable for jungle fighting in the Pacific theatre. A more versatile two-part system called the M-1941 Haversack was devised. This comprised an upper "marching pack" for rations, poncho and clothes, and a lower knapsack for extra shoes and utilities. The exterior of the upper pack had loops and grommet tabs for attaching a bayonet, shovel, bedroll, extra canteen, and first-aid pouch. Originally issued in tan or khaki canvas, a slightly modified olive drab version was introduced in 1943.
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