Complex sentence: On the death of their contractor, Francis Tredwell, work stopped for several years while they entered into long litigation with his family firm over financial claims; it took the intervention of Brunel before they released monies that allowed his brothers to continue work in 1851.
Split into simpler sentences: On the death of the contractor, Francis Tredwell, work stopped for several years while the Company entered into long litigation with his family firm over financial claims. It took the intervention of Brunel before they released monies that allowed his brothers to continue work in 1851.