Complex sentence: He probably devised, and certainly presented, the silver caduceus now in the possession of Caius College as part of its insignia; he first gave it to the College of Physicians, and afterwards presented the London College with another.
Split into simpler sentences: He probably devised, and certainly presented, the silver caduceus now in the possession of Caius College as part of its insignia. He first gave it to the College of Physicians, and afterwards presented the London College with another.