Turner's example problem number sixteen:  Determining the distance of the moon from the earth.

Richard Turner, an English author, wrote a series of books throughout his life pertaining to various fields of scientific discovery.  This presentation expands on three of his writings in these areas of study which, in this case, were bound together as a collection.  These works include:

• A View of the Heavens: Being a Short, but Comprehensive System of Modern Astronomy

• A View of the Earth: A Short but Comprehensive System of Modern Geography

• Plain Trigonometry Rendered Easy and Familiar, by Calculations in Arithmetic Only

The book itself is 9”X14” and, although there is considerable damage to the outer cover, the pages contained within, aside from discoloring due to aging, remain in excellent condition.  This is because of the quality of paper being higher than typically used at the time and the calf skin cover providing protection against the outside world.  Along with diagrams, maps and illustrations throughout the entire book, moving dials are also found within the pages so as to further demonstrate the topics being discussed, such as the positions of the constellations in the sky on any given day.  

Many of the scientific discoveries being presented within the pages of these works can be credited as using the very techniques that he outlines.  For example, in the Plain Trigonometry section, Turner outlines the technique for using triangles and the angles of these triangles in order to calculate the distance to the Moon (this problem is illustrated in the picture above).  This, and many other discoveries presented in this book, were found using the very mathematical formulas that he addresses in the Plain Trigonometry section.