With the map is given a view of the strata of rocks from Hoosack mountain to eleven miles east of Connecticut river, on a line nearly east and west, passing through Deerfield. The horizontal distances are laid down from a scale: the elevations are assumed. The principal rocks only are coloured; for it is very difficult to determine the breadth of many, since they frequently alternate with one another. I have not examined the country on the east side of Connecticut river with sufficient care to be able to extend the section on that side more than a few miles. It may not be amiss to mention, that Mount Holyoke, so much celebrated for the delightful view from its top, has been found, with a sextant, to be 830 feet above Connecticut river. Its height has been frequently overrated. The mineralogy of this section of the country has been but imperfectly explored. I shall mention those minerals only of which I have obtained specimens, and whose localities have not been noticed by mineralogists. _Quartz_--several varieties. 1. _Rock Crystal_--abundant. Some good specimens are found in Conway, on feldspar, with the usual hexagonal, prismatic crystals, and these crystals cross each other in all directions. 2. _Irised Quartz_--found in Leyden. 3. _Granular Quartz_--in Deerfield. 4. _Radiated Quartz_--in Whately and Shelburne. 5. _Blue Quartz_--in rolled masses on the banks of Deerfield river. 6. _Greasy Quartz_--in same place. 7. _Pseudomorphous Quartz_--in greenstone, Deerfield. 8. _Lamellar Quartz_--in same place. The laminæ sometimes penetrate crystals of common quartz. 9. _Tubular_, or _Pectinated Quartz_--in same place. 10. _Quartz Geodes_--in same place. _Prase_--in the north part of Sunderland. (Not good specimens.) _Amethyst_--in Greenstone, Deerfield: the colour is not deep, but delicate. _Chalcedony_--in same place--considerably abundant, but generally in small masses. _Carnelian_--in same place, not plenty. The chalcedony, in some specimens, seems to be passing into cacholong, and the carnelian into sardonyx. _Agate_--in same place. It is made up of chalcedony, carnelian, and quartz. They are generally small, but some are elegant. _Jasper_, red, and yellow--found in rolled masses on the banks of Deerfield river and in Leyden. Some have been found imperfectly striped. It occurs frequently as it was formed by the aboriginals into barbs for pikes and arrows. _Petrosilex_--on the banks of Deerfield river--not good specimens. _Feldspar_--the red variety occurs in puddingstone, Deerfield. It is not necessary to mention any other locality of a mineral so common. _Hornblende_--very abundant--mostly black in this vicinity. _Mica_--this is very abundant on the east side of Connecticut river. Some crystals of it have been found in Amherst. _Talc_--in Shutesbury. _Steatite._ The localities of this are seen on the section. The aboriginals formed many articles from this mineral, as pots, pipes, &c.