Sheldon Sc Co. and Spurgeon.—A letter just received from Sheldon Co., by S. Boykin, Agent, contains the following, which we publish in justice to them. It shows that they are not anti-slavery.In regard to Spurgeon, we have only to say that his letter in the Watchman lt;Sc Reflectorsurprised us as much as it did you. We had no knowledge of it whatever until we saw it in the paper. You know well it does-not express our sentiments ; and what he says about our publishing everything that hp may chooseto write, you see at once that the idea is preposterous. We do not so promise to anybody.SHELDON CO.