Found the following article online, use it to answer the question: The leakage of what was partly caused by being pressed too much with sail?

The departure of the Mayflower and Speedwell for America was beset by delays. Further disagreements with the Merchant Adventurers held up the departure in Southampton. A total of 120 passengers finally departed on August 5—90 on the Mayflower and 30 on the Speedwell. Leaving Southampton, the Speedwell suffered significant leakage, which required the ships to immediately put in at Dartmouth. The leakage was partly caused by being overmasted and being pressed too much with sail. Repairs were completed, and a further delay ensued as they awaited favorable winds. The two ships finally set sail on August 23; they traveled only two hundred miles beyond Land's End before another major leak in the Speedwell forced the expedition to return again to England, this time to the port of Plymouth. The Speedwell was found to be unseaworthy; some passengers abandoned their attempt to emigrate, while others joined the Mayflower, crowding the already heavily burdened ship. Later, it was speculated that the crew of the Speedwell had intentionally sabotaged the ship to avoid having to make the treacherous trans-Atlantic voyage. The delays had significant consequences; the cost of the repairs and port fees required that the colonists sell some of their invaluable provisions. More importantly, the delays meant that everyone had to spend the entire winter on board the Mayflower off Cape Cod in what could only be described as squalid conditions.

Speedwell