7 5 0 – 1 8 8 5 ▁( 1 9 9 3 ) ▁ ▁Further ▁reading ▁ ▁G . ▁R atten bury ▁and ▁M . J . T . ▁Lewis . ▁Mer th yr ▁T yd fil ▁Tr am ro ads ▁and ▁their ▁Lo comot ives ▁( R ail way ▁& ▁Canal ▁Historical ▁Society , ▁ 2 0 0 4 ). ▁ ▁External ▁links ▁ ▁Old ▁Mer th yr ▁T yd fil : ▁Pen yd ar ren ▁– ▁Historical ▁Phot ograph s ▁of ▁Pen yd ar ren . ▁Old ▁Mer th yr ▁T yd fil : ▁Pen yd ar ren ▁Iron works ▁– ▁Historical ▁Phot ograph s ▁of ▁Pen yd ar ren ▁Iron works . ▁Old ▁Mer th yr ▁T yd fil : ▁Pen yd ar ren ▁Lo comot ive ▁– ▁Historical ▁Phot ograph s ▁of ▁the ▁' P en yd ar ren ▁Lo comot ive '. ▁ ▁Category : Build ings ▁and ▁structures ▁in ▁Mer th yr ▁T yd fil ▁Category : Ind ust rial ▁history ▁of ▁Wales ▁Category : I ron works ▁and ▁steel works ▁in ▁Wales ▁Category : Rich ard ▁Tre v ith ick <0x0A> </s> ▁Oliver ▁D . ▁Cris p ▁( born ▁ 1 9 7 2 ) ▁is ▁a ▁British ▁the olog ian ▁who ▁currently ▁works ▁as ▁Professor ▁of ▁Anal yt ic ▁The ology ▁at ▁the ▁University ▁of ▁St . ▁Andrew s , ▁and ▁was ▁formerly ▁a ▁professor ▁of ▁system atic ▁the ology ▁at ▁Full er ▁The ological ▁Sem inary ▁in ▁Pas ad ena , ▁California .