-- At the opening of the Sanitary Fair in St. Louis, a few days since, Gen. ROSECRANS made a speech, in the course of which he said:

"Now there is one little matter that I wish to call your attention to: I understand, in a discussion sometime ago the question of having raffles was up, and I understand the decision was against raffles. I want to say that I think that is a great mistake, and I will give you my reasons. In the first place. I understand the main objection to the raffling business was that it was gambling. Well, in that sense, I would not advocate it; but this is not in the nature of gambling at all. Here, for instance, are many articles contributed to the fair, such as furniture guns, robes, furs and articles of high prices which probably may have been donated, but you cannot get purchasers for them. No one man wants to buy them. A man comes to the fair not to make money. He comes with twenty-five and dollars, intending to spend it. He comes along, and probably a nice little girl asks him to take a share in a lot of furniture or something of that sort -- five dollars or so, and he is ready to give it, as all of us would be too oblige our little friends; but he would not care to pay for the fall value of the article. I think it is a grand mistake not to allow articles to be disposed of by shares, or you may call it what you please. I am certain that people do not attend these fairs with the view of buying articles for speculation, and when they give two or five dollars for a share in some article, it is just as much a charity as if they gave it out. So I am certain the arrangement has no immortality in it, but it merely facilitates the disposal of these articles. I think it will be a great loss to us if we do not adopt that plan, and I take occasion to say it because of my experience. As has been said. I think the honor and credit of your City and business, warrants you in expecting a handsome result from your fair. I think the result will be taken as an evidence of your public spirit, and your business capacity. As has been remarked, I think that if St. Louis does not make a good showing in regard to this fair, the people abroad will think the business men here a poor set of fellows, and will not care to trade with them; but if you show a liberal spirit they will say you are an enterprising people, and they will trade with you, You have a large city, destined to be one of the very largest. Your roads are being opened to the West, and you ought to expand your trade, and you ought to show the country that you are public spirited and that when you undertake to do a thing, you don't do it by halves; and from what I have seen this evening I don't think your prospects are bad at all, and I have no doubt you will succeed as amply as you have any right to expect." [Applause.]