Complex sentence: Art critic Nikolaus Pevsner described the building as possessing a "rare picturesque beauty", while its stained glass windows, some of which were designed by William Morris, are credited as "the finest modern examples of their kind".
Split into simpler sentences: Art critic Nikolaus Pevsner described the building as possessing a "rare picturesque beauty". Its stained glass windows, some of which were designed by William Morris, are credited as "the finest modern examples of their kind".