这里的获知为何用了give of 呢？

Incredible as it may appear to you, Mr. Holmes, he was honestly convinced that a dreadful fate overhung his family, and certainly the records which he was able to give of his ancestors were not encouraging.

书上的翻译和英文原意是：他从祖辈那里获知的故事确实叫人情绪沮丧，那样对应就是上文中的give of...为何这里的give of会有“获知“的意思呢？

麻烦老师解说一下。谢谢！

and分句主干为：the records were not encouraging

the records（记载）有两个定语

1. which he was able to give他可以给出的

2. of his ancestors关于他的祖先的

也就是说：他能给出的（当然就是当时他所获知的）关于他的祖先的那些记录。译文可能为了全文的流畅调整了中文的表达。give of不是短语动词。