Complex sentence: Probably near Pukapuka (Cook Islands) it met another slaver, the "General Prim", which had left Callao in March, which was more than willing to take over the 174 Tongans to quickly return to port, where it arrived on 19 July.
Split into simpler sentences: Probably near Pukapuka (Cook Islands), it met another slaver, the "General Prim", which had left Callao in March. Its captain was willing to take over the 174 Tongans to quickly return to port, where it arrived on 19 July.