Complex sentence: In 1840, Gavarret and Gabriel Andral (1797-1876) were the first to show that blood composition varied depending on the pathological condition of the subject, and their research demonstrated the value of animal chemistry as a means of confirming diagnoses.
Split into simpler sentences: In 1840, Gavarret and Gabriel Andral (1797-1876) were the first to show that blood composition varied depending on the pathological condition of the subject. Their research demonstrated the value of animal chemistry as a means of confirming diagnoses.