 Construction work went ahead under the supervision of the Consulting Engineer , George Parker Bidder . By February 1847 there were 1 @,@ 318 men and 60 horses working between Macclesfield and Colwich and they had removed 80 @,@ 000 cubic yards ( 61 @,@ 000 m3 ) of earth , driven 843 yards ( 771 m ) of tunnel heading and erected 12 @,@ 000 yards ( 10 @,@ 973 m ) yards of fencing . 
