Speaking of Dinosaurs

Venture SF #13 Most people accept Darwin's theory of evolution. Well David Standing did... until one day he wandered by chance into a museum and saw the dinosaur. As a gifted engineer his enquiring mind made him question how such a massive skeleton had been able to balance and move; his experiments proved it was impossible. Then attempts were made on his life... And, in a horrifying time shift, back to the distant past, he visits Primeval Earth - where, naked and unarmed, he comes face to face with the truth about the evolution of man...