Shepherd's whistle
They are also produced commercially. Simple whistles may cost less than 1 USD in bulk; expensive ones may be quite ornate. They are commonly made of plastic, aluminum, stainless steel, silver, brass, titanium, Corian, jade, buffalo horn and other materials.
Slide whistle
The swanee whistle dates back at least to the 1840s, when it was manufactured by the Distin family and featured in their concerts in England. Early slide whistles were also made by the English J Stevens & Son and H A Ward. By the 1920s the slide whistle was common in the USA, and was occasionally used in popular music and jazz as a special effect. For example, it was used on Paul Whiteman's early hit recording of "Whispering" (1920). Even Louis Armstrong switched over from his more usual cornet to the slide whistle for a chorus on a couple of recordings with King Oliver's Creole Jazz Band, such as "Sobbin' Blues" (1923). At that time, slide saxophones, with reeds rather than a fipple, were also built. The whistle was also widely used in Jug band music of the 1920s such as Whistler's Jug Band. Gavin Gordon uses a slide whistle in his ballet "The Rake's Progress" (1935).