What is the meaning of The riven masts had gone by board in Swiss Family Robinson?

The phrase "riven masts had gone by board" in "Swiss Family Robinson" means that the masts of the ship had been broken and fallen overboard.

Here's a breakdown:

* Riven: This means "split or torn apart," likely due to a storm or other forceful event.

* Masts: These are the tall vertical poles on a ship that support the sails.

* Gone by board: This means "fallen overboard" or "washed away."

Therefore, the phrase describes a significant damage to the ship, where the masts were broken and lost. This would be a major setback for the Swiss Family Robinson, who relied on their ship for transportation and survival.