Tennis balls

Hey guys, doing something a little different today, its too hot and i know i havent posted in a while. So im going to give you guys information on Tennis Balls. Because i feel like it, and its my blog. :)
 Tennis balls are used for a variety of reasons. Some play games called; Matscot, Itallian Handball, and three square. Other people give them to their pets to shred, most of the time they are a durable ball, able to withstand massive amounts of pressure, and so the ideal dog toy. Unfortunately, some dogs mastered the art of shredding these balls long ago, and some larger dogs can choke on the balls. 
 Tennis balls are made from roughly three simple materials, a hollow inside is surrounded by rubber, the thing that makes it bounce high. This is then coated in a thin layer of Adhesive, and felt, usually neon yellow as it was tested as the most visible on a colour tv, is stuck onto the outside.
 Tennis balls have to be certian sizes and weights, they have to have a diameter of 65.41mm - 68.58mm and a weight of 56.0g to 59.4g
 Felt in these modern days is made of wool, mixed with synthetic. Felt is one of the oldest textiles, and is around 5000 years old. Its added to a Tennis ball as it 'Delays flow separation in the boundary layer, reducing aerodynamic resistance' this basically means it goes faster through the air.
 Rubber comes from any plant or tree that excretes the milky white substance instead of sap, but most rubber comes from the Hevea tree in Brazil, Brazils rubber tree. 

Pressurized tennis balls, those that come in tightly packed bunches, begin to loose their bounce as soon as the package is opened, so often they are kept pressurized until the consumer buys them, unpressurized ball however do not loose their bounce over time, in fact they gain more bounce, becoming lighter as they bald, allowing them less resistance against the wind.
 They tend to come in packages of three or more, and often cost 50p, but prices vary. 
Thats about all i have to say now really. :)