Complex sentence: In 1851 August Heinrich Petermann introduced Vogel to the Royal Geographical Society and in 1853 Petermann arranged for Vogel to join the Richardson, Overweg and Barth expedition that had been sent to Africa in 1849 to find a trade route that bypassed the Arabs.
Split into simpler sentences: In 1851 August Heinrich Petermann introduced Vogel to the Royal Geographical Society. In 1853 Petermann arranged for Vogel to join the Richardson, Overweg and Barth expedition that had been sent to Africa in 1849 to find a trade route that bypassed the Arabs.