What is the doctors advice to silver?

The Doctor actually gives Silver a few pieces of advice.

Silver!" he cried. "Silver! I'll give you a piece of advice," he continued as the cook drew near again; "don't you be in any great hurry after that treasure."

"Why, sir, I do my possible, which that ain't," said Silver. "I can only, asking your pardon, save my life and the boy's by seeking for that treasure; and you may lay to that."

"Well, Silver," replied the doctor, "if that is so, I'll go one step further: look out for squalls when you find it."

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"My second is a piece of advice: keep the boy close beside you, and when you need help, halloo. I'm off to seek it for you, and that itself will show you if I speak at random. Good-bye, Jim."