God gives us the earth and the seed, but we must plough and sow, or we can never reap; so he has bountifully placed within our reach innumerable valuable rocks, minerals and combustibles, but to enjoy them, we must delve into the bowels of the earth--and having found them, we must, by various laborious processes, render them fit for our use. To those who are accustomed to regard these things, it is difficult to determine which causes the most painful sensations, to observe how few coal mines, in comparison to what might be, are opened in the neighborhood of Richmond, or the want of skill exhibited in the selection and working of those recently opened. Nor is the deposite of the bituminous coal upon the granite, the only geological anomaly of this quarter. Proceeding from Charlottesville towards Richmond, almost immediately after you leave the Talcose formation of the Blue Ridge, you are astonished at the fertility of the soil; you can scarcely persuade yourself that you are travelling over a country of primitive rocks. Soon, however, you discover that the fertility is not universal, but confined to patches of a brick-red covering, that overlay the disintegrated materials of the primordial formations, and upon seeking further into this curious matter, your surprise is not a little increased, upon discovering that this brick-red covering owes its existence to the disintegration of a rock, which, in most other places, is exceedingly slow to decompose, and which, when decomposed, forms a cold and inhospitable soil. It is the _hornblende sienite_. Here it is surcharged with iron, which oxidating by exposure to the atmosphere and moisture, the rock freely disintegrates, and the oxide of iron being set at liberty, imparts its coloring to the ground, and fertilizes the soil in an extraordinary degree. Professor Hitchcock, in his report of a geological survey of Massachusetts, makes the following remarks in relation to the effect of iron upon a soil: