Complex sentence: As the chief was walking along the water he spotted Carlos de Sigüenza y Góngora attempting to reef his sails and offered to guide Siquenza and his men to a connecting deep water channel from the Gulf of Mexico into the more tranquil bay.
Split into simpler sentences: As the chief was walking next to the water, he spotted Carlos de Sigüenza y Góngora attempting to reef his sails. He offered to guide Siquenza and his men to a connecting deep water channel from the Gulf of Mexico into the more tranquil bay.