It looks like this is actually a quote from Carolyn Merchant's The Death of Nature; only the parts in quotation marks are Bacon's words, taken from "The Great Instauration", "The Masculine Birth of Time", and "De Dignitate".
Confirmed from the linked Amazon.com page by searching the preview for "searchers and spies of nature" (no quotes).
This is our monthly thread for collecting these little gems and pearls of wisdom, rationality-related quotes you've seen recently, or had stored in your quotesfile for ages, and which might be handy to link to in one of our discussions.