Page:Transactions of the Geological Society, 1st series, vol. 4.djvu/213

 many cwts. in the fields between Ham Green and Leigh, and I am inclined to believe that these are derived from the red loam which lies between the two beds, for I found a mass of it in a ditch lately dug on the slope of the hill below the basset of the upper breccia; but the circumstances were not altogether decisive. The sulphate of strontian from this place is seldom found well crystallized, the best of the crystals that I have met with being tables not exceeding$$\scriptstyle \frac 14$$th of an inch in length. The entire masses are generally snow white, having the appearance of a coarse grained loaf-sugar, but sometimes they acquire a reddish hue from a small quantity of ochre.

Small veins of galena are found in the breccia. The breccia is found near to Abbot's Leigh, from whence it extends in a position almost horizontal to Crokerne; and it probably occupies the whole space included by a line drawn from Leigh through Failand, Charlton, Portbury and Portishead, and thence returning again through Crokerne to Leigh. On the opposite side of the river it forms the stratum beneath Shirhampton, and runs up the valley below King's Weston hill, extending to the cast as far as Sneed Park. In some parts it is found at so high an elevation as to lead to a belief that there may be more than two beds of the breccia: in whatever situation however it is met with its general characters are the same.

The red loamy earth at Hung-road is traversed by veins of fibrous carbonate of lime, which are about an inch thick, and contains hollow calcareous nodules which are often lined on their inner surfaces with beautiful calcareous and siliceous crystals. The quartz varies but little in form; it is almost always in very short six-sided prisms terminated by two six-sided pyramids. It sometimes contains acicular crystals of iron ore: is generally transparent and colourless, but sometimes assumes an amethystine tint. The calcareous crystals vary very much in form, sometimes exhibiting that of the primitive