Harris-burg seems to be an unlucky place, if a "treatise on insects " from that quarter, which is now before us, is to be fully credited. The people there do not seem to do as they ought to do, the writer seems to think. He tells us that he learned in Cincinnati, in 1867, that by placing marble dust the full extent of the branches on the ground under a plum tree, the result will be perfect security from the curculio. Now it seems to us that if the gentleman has faith in what he tells the Harris, burg people, it would be a very profitable thing to invest in a plum orchard and treat it on this plan. But it is easier to preach than to practice, except where medicine is concerned. The gentleman takes care to tell us in this treatise on insects, that he is a physician, and that "over 3,500 persons have visited my office in 17 months, who, with a few exceptions, have been ill for years." As this makes six every day without counting the number " over," and this is but one physician; if we could only get at the long list that visit others, and the list who are too sick to visit and have to be visited, it would seem that Harrisburg, between politicians, insects and physicians, must be a frightful place.