Complex sentence: The "Second Kamchatka Expedition" took place in 1735--42, with two ships, "Svyatoy Pyotr" and "Svyatoy Pavel", the latter commanded by Bering's deputy in the first expedition, Captain Aleksey Chirikov.
Split into simpler sentences: The "Second Kamchatka Expedition" took place in 1735--42. This time there were two ships, "Svyatoy Pyotr" and "Svyatoy Pavel", the latter commanded by Bering's deputy in the first expedition, Captain Aleksey Chirikov.