The earliest example of equine footwear we have is made of animal hide and dates from about 600 B.C. This primitive hoof protector looks more like a horse bootie than what we think of today as a horseshoe. It was probably stuffed with dried grass or other available natural material and tied on with hide thongs.
The spiral model is a software development process combining elements of both design and prototyping-in-stages, in an effort to combine advantages of top-down and bottom-up concepts. The spiral model was defined by Barry Boehm in his article A Spiral Model of Software Development and Enhancement from 1985. This model was not the first model to discuss iterative development, but it was the first model to explain why the iteration matters.
A first âsolutionâ was announced in 1919, by William Romaine Newbold (Newbold, 1921), who caused a sensation by claiming that the manuscript did indeed contain the work of Roger Bacon and that Bacon had known the use of the compound telescope and microscope, seeing the spiral structure of the Andromeda galaxy* (!) only visible with modern telescopes and cell structures unknown in the 13th Century.