User:Ykraps/Sandbox 3

Weymouth table

Historical population of Weymouth
Year	1901	1911	1921	1931	1941	1951	1961	1971	1981	1991	2001	2011
Population	19,843	22,324	24,556	22,188	38,527	37,099	41,045	42,370	45,090	48,350	50,920	52,266
Sources: Great Britain Historical GIS. Dorset County Council

The Darts

Initially the missiles were simply cut down arrows or crossbow bolts. The first purpose made darts were manufactured in one piece from wood; wrapped with a strip of lead for weight and fitted with flights made from split turkey feathers. These darts were mainly imported from France and became known as French darts. Metal barrels were patented in 1906 but wood continued to be used into the 1950s. The first metal barrels were made from brass which was relatively cheap and easy to work. The wooden shafts, which were now threaded to fit the tapped barrel, were either fletched as before or designed to take a paper flight. This type of dart continued to be used into the 1970s. When the advantages of using plastic were realised, the shaft and flight became separate entities, although one piece moulded plastic shaft and flights were also available.

Modern darts have four parts: The points, the barrels, the shafts and the flights. The steel points come in 2 common lengths, 32mm and 41mm and are sometimes knurled or coated to improve grip. Others are designed to retract slightly on impact to lessen the chance of bouncing out.

The barrels come in a variety of weights and are usually constructed from brass, silver- nickel or a tungsten alloy. Brass is cheap but light and therefore brass barrels tend to be very bulky. Tungsten on the other hand, is twice as dense as brass thus a barrel of an equivalent weight could be half the size. Tungsten is very brittle however and so an alloy of between 80 - 95% tungsten is used. The remainder is usually nickel, iron or copper. Silver-nickel darts offer a compromise between density and cost.

Barrels come in 3 basic shapes: Cylindrical, torpedo or ton. Cylindrical barrels are the same diameter along their entire length and so tend to be long and thin. Their slenderness makes them better for grouping but because they are long, the centre of gravity is further back. Ton shaped barrels are thin at either end but bulge in the middle. This makes them fatter than a cylindrical barrel of equivalent weight but the centre of gravity is further forward and so theoretically easier to throw. Torpedo shaped barrels are widest at the point end and taper towards the rear. This keeps the weight as far forward as possible but like the ton, gives it a larger diameter than the cylinder.

The shafts are manufactured in various lengths and some are designed to be cut to length. Shafts are generally made from plastics, nylon polymers or metals such as aluminium and titanium; and can be rigid or flexible. Longer shafts provide greater stability and allow a reduction in flight size which in turn can lead to closer grouping; but they also shift the weight towards the rear causing the dart to tilt backwards during flight. A longer stem will however make the dart less responsive and increase the chance of 'wobbling'.

The primary purpose of the flight is to produce drag and thus prevent the rear of the dart overtaking the point. Although it also has an effect on stability by reducing wobble. Modern flights are generally made from plastic, nylon or foil and are available in a range of shapes and sizes. The three most common shapes in order of size are the standard, the kite and the smaller pear shape. The less surface area, the less stability but larger flights hamper close grouping. Some manufactures have sought to solve this by making a flight long and thin but this in turn creates other problems such as changing the dart's centre of gravity. Generally speaking a heavier dart will require a larger flight.

The choice of barrel, shaft and flight will depend a great deal on the individual player’s throwing style. For competitive purposes a dart cannot weigh more than 50g including the shaft and flight and cannot exceed a total length of 300mm.