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t 58 REPORT OF THE VERMONT STATE GEOLOGIST. iorphic individuals bounded by prismatic and pinacoidal planes. They are characterized by the development of a zonal structure, with inclusions of the ground-mass stage in the outermost zone. Plagioclase crystals are occasionally noted, not glassy but much weathered. They are rare, however, and small. The biotite does not differ in habit from that mineral in the granite. Irregular grains of titanite and needles of apatite are found. Touching the above, and at the sides of the V, is developed the facies of the rock in which no hiotite is present. Hand specimens show silvery scales of muscovite in great abundance, making, with glassy feldspar and quartz, a very fine-grained rock with no ground-mass. Microscopical study reveals the presence of glassy microcline as the predominant feldspar, with much less of plagioclase and quartz, these last being in nearly equal amounts. A little orthoclase is also present. Muscovite, in large patches and scaly aggregates, is extraordinarily abundant. Magnetite and apatite occur in large grains. Occasionally small pieces of pyrite may he observed. The extremely coarse-grained facies exhibits only biotite and feldspar to the tinaideci eye. The biotite is in thin brownish black leaves which are often 2 cm. in diameter. The feldspar is bluish gray. It does not appear to be tvinned, and on its flashing cleavage faces no striations can be detected. The single pieces of massive feldspar are often 3 cm. across. When viewed under the microscope the rock is seen to be made up of microcline and hiotite. The feldspar is very generally characterized by the usual delicate twinning lamellae of microcline, and it is intergrown with quartz as in graphic granite. The crystals of quartz are often .8 mm. in length. They present triangular, spike-like, or more complicated forms.. They may be readily recognized by their interference colors as compared with those of the feldspar, and they are large enough to answer to tests with convergent light. They extinguish simultaneously. Small crystals of plagioclase are also enclosed 4' REPORT OF THE VERMONT STATE GEOLOGIST. 59 by the microcline. Much chlorite has resulted from the weathered condition of the mica. The granite industry at Barre, Vt., is of comparatively recent development. As far back as 1833 blocks of stone were drawn by ox teams to Montpelier to furnish the granite columns of the capitol, but the period of active work on Millstone Hill dates hack only a score of years. It was the order for ten million paving blocks for the city of Troy which first stimulated activity on the hill. Now 2,000 quarrvmen are engaged to work there. The quarrying operations have been conducted with extraordinarv energy and ability. Before the introduction of steel hoisting machinery derrick sticks of wood, ninety feet in length, were brought from Oregon. The most improved appliances .are used in the shops at Barre for shaping the stone. The sheds for working under cover at a nearly constant temperature summer and winter are the largest in the world. The gray granite of Barre is remarkable indeed for its evenness and beauty in the rough and in polished pieces. Its qualities of resisting the agencies of weathering, and of continuing to look clean and bright after exposure, are greatly in its favor. It has become famous as well for its wonderful adaptability to tool treatment. On the singularly beautiful monumental stone over the grave of the two Gobbi children in the cemetery to the west of the city an armful of roses and lilies has been carved in the round with matchless skill. Such work would have been wonderful in marble. The monument to Robert Bur.ns in the city of Barre, with its statue of the poet, and pedestal covered by illustrative tablets, is probably the noblest piece of granite carving to be found in any city.
6o REPORT OF THE VERMONT STATE GEOLOGIST. Through the courtesy of Dr. C. H. Richardson, of Dart mouth College, I am able to publish, in addition to the special discussion of the Barre granites which Mr. Finlay's paper furnishes, a more extended account of the geology of Washington county, in which are located most of the important granite areas of the State, though others to the north and south are not to be overlooked, and particularly of Orange county, in which the Washington limestone is especially displayed, and also of Windsor county. While Dr. Richardson does not primarily consider the granites, yet as these necessarily receive much attention, the paper naturally should be included in a discussion of Vermont granites. By these contributions we are furnished with a much more accurate and complete account of the region involved than has ever been published. It may be proper to state that the papers are published as they came from their authors, and, therefore, they alone are responsible for such statements and conclusions as they contain
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