The Mechanics Calculator By William Grier Twentieth Edition Victorian rare book

A book from the Victorian era.
 
This book I can not understand, but there are those that understand this.
 
The book has maths equations, diagrams of mechanics and so much more, I do not understand this therefore this listing is short.
 
This book is damaged, the book is antique, the book was leather bound, since then it has been covered and repaired with some brown tape.
 
More great books at Prelovedbargains Etsy: https://www.etsy.com/uk/shop/Prelovedbargains?ref=seller-platform-mcnav
 
And 
 
BoutiquebyRachelco: https://www.etsy.com/uk/shop/BoutiquebyRachelCo?ref=seller-platform-mcnav