9. _Compact Limestone._ In several places low in the valley. Near the college it is white and deep gray. In the veins of the latter, _talc_ is diffused in all directions. It contains silex, often from 3 to 15 per cent., and sometimes gives fire with steel. In some cases it is earthy. On Green River, one and a half mile south of the college, it lies in thin strata, which are divided by seams into very regular rhomboidal plates of various sizes. On some scattered fragments on this river, are found carbonate of lime in crystals, with pieces of white feldspar. On West Brook, this gray limestone is traversed by a vein of quartz, containing sulphuret of iron. The strata of this rock are almost invariably inclined to the east. A coarse _soapstone_ is found in the limestone near the college, and a vein made up of brown argillaceous slate, soapstone, quartz, and sulphuret of iron, passes through it. This limestone appears to be very different from that at the base of Saddle Mountain, and from that which yields the marble of Berkshire county. It may still be _primitive_, but _primitive compact limestone_. 10. _Granitell_ of Kirwan, _Quartz_, and _Feldspar_. This aggregate forms extensive strata at the east base of Stone Hill. The feldspar is diffused in grains through the quartz, and sometimes crystalline, forming _porphyritic quartz_. This aggregate is often compact and very hard, but frequently it is porous and hard, forming good millstones. Sometimes the quartz appears in such fragments, that the stone resembles _breccia_. 11. _Black Tourmaline._ In beautiful small six-sided prisms, in scattered pieces of mica slate at the base of Stone Hill. 12. _Amianthus._ Only a small specimen, attached to _argillaceous slate_. 13. _Bitter Spar._ On compact limestone at West Brook. Some of the crystals are rhomboids, and some appear to be the half of rhomboids split through their longer diagonal. 14. _Jasper._ The common brown or red, and black, in small rounded masses, and also a piece of variegated or striped jasper. 15. _Galena._ Only a specimen in the limestone on West Brook. 16. _Iron Ore._ _Bog ore_ on the Hoosack, a mile northeast of the college. _Yellow earth_, from which _yellow ochre_ is obtained in great quantity, in a hill (R) on the bank of Green River, 2 miles south of the college. At the north end of Saddle Mountain, but low down, yellow earth is connected with _reddle_, or a substance much resembling it. It is less hard than the common reddle, but is composed of the same ingredients. _Magnetic Oxyd of Iron_, regular octahedrons, in mica slate at the base of Stone Hill. _Supersulphuret of Iron_, massive and crystallized, in argillaceous slate, mica slate, compact limestone, and quartz. 17. _Prase._ Beautiful, and containing sulphuret of iron; lately found by Mr. Eaton, a little east of the summit of Hoosack Mountain, in Florida.