Complex sentence: On the second voyage of the "Clontarf" 41 people died including five adults, but also 36 children, and that was to give "Clontarf" her infamy.
Split into simpler sentences: On the second voyage of the "Clontarf" 41 people perished. Among the dead were five adults, but it was the large amount of children death that was to give "Clontarf" her infamy.