Beeswax mixture fills mast checks
The main mast, like every wooden mast, has “checks,” or superficial cracks. Wood expands, contracts and flexes with weather and strain. Cracks form over time, usually with the grain of the wood. Checks do not necessarily compromise the strength of the mast when they are relatively small. One way to keep them small is to fill them with a mixture of substances that will keep water out while still allowing the wood to flex. Beeswax is a substance sailors have used for that purpose for centuries and we used it, too. The trick is to make sure the entire crack is completely filled. So the crew applied more and more of the mixture over time, allowing it to seep as deeply as possible.