Those who visit the metal works of Birmingham naturally desire to know where the metals come from; and especially the precious metals. Among the materials shown to the visitor, are drawers full of the brightest and cleanest gold; and ingots of silver, pure, or slightly streaked with copper. We have handled to-day an ingot which contains, to ninety-two ounces ten pennyweights of silver, seven ounces ten pennyweights of copper. We ask whether the gold comes from California; but we find that it has just arrived--from a much nearer place--from a refinery next door. We hear high praises of the Californian gold. It is so pure that some of it can be used, without refining, for second-rate articles. Some small black specks may be detected in it, certainly, though they are so few and so minute, that the native gold is wrought in large quantities. But what _is_ this neighboring refinery? Whence does it obtain the metals it refines? Let us go and see. It is a strange murky place; a dismal inclosure, with ugly sheds, and yards not more agreeable to the eye. Its beauties come out by degrees, as the understanding opens to comprehend the affairs of the establishment. In the sheds, are ranges of musty-looking furnaces; some cold and gaping, others showing, through crevices, red signs of fire within. There are piles of blocks of coal, of burnt ladles and peels, and rivulets of black refuse, which has flowed out from the furnaces into safe beds of red sand. In a special shed, is a black moist-looking heap of what appears to be filth, battened into the shape of a large compost bed. A man is filling a barrow with this commodity, and smoothing it down with loving care. And well he may; for this despicable-looking dirt is the California of the concern! Here is their gold mine, and their silver mine, and their copper mine. In another shed, is a mill-stone on edge, revolving with the post to which it is fixed, to crush the material which is to be calcined. In the yard, we see heaps of scoriæ--the shining, heavy, glassy-looking fragments, which tell tales of the prodigious heat to which they have been subjected. We see picks, and more ladles, and lanterns, and a most sordid-looking bonfire. A heap of refuse is burning on the stones; old rags, fragments of shoes, cinders, dust, and nails--the veriest sweepings that can be imagined. Something precious is there; but the mass must be burned to become manageable. The ashes will be swept up for the refinery. But what is it that yields gold, and silver, and copper, and brass? What is that heap of dirt in the special shed? It is the sweepings of the Birmingham manufactories.