A mincing knife was used to cut a piece of blubber into smaller, thinner slices, while it was still connected to the skin. After it was cut, it resembled pages in a book. The whalers called these "bible leaves". This process made it easier to render the oil from the blubber, a process known as "trying" the oil. This mincing knife was used on the Bark Bertha from New Bedford, on January 15, 1878.