THE FARMER'S MONTHLY VISITOR. 



17 



Having seen all that was deemed essential to 

 our purpose, we retm-ued to Poitsmoutli, and 

 continued onr lesearclies in the vicinity of the 

 town. 



GEOLOGV OF PORTSMOUTH AND ITS VICINITV. 



The Geology of Portsmouth is somevvliat com- 

 plicated and difficult, but possesses a high scien- 

 tific inteiest. 



The principal rocks are of a metamorphic 

 character, or such as have undergone marked 

 changes in structure or composition, by the agen- 

 cy of heat. They are continuations of similar 

 strata which occur at York, in the State of Maine, 

 and exhibit like phenomena. 



The rocks to which I refer are the dark blue 

 flinty slates, possessing an imperfectly stratified 

 structure — a vei^ compact texture — sonorous 

 when struck by the hammer, and often breaking 

 with a more or less distinctly conchoidal fracture. 

 Occasionally they evince a pas.sage into an imper- 

 fect giicaceous slate, especially where they bor- 

 der on granite rocks. 



The strata were doubtless originally deposited 

 in a horizontal position, and were formed by the 

 deposition of clayey ])articles from water. In its 

 first stage, the matter was probably in the state of 

 fine blue clay, but when the eruption of the gran- 

 ite and trap rocks took place, the clay became 

 hidurated, and was converted into solid rock, 

 while the strata at that epoch were tilted up and 

 set on tlicir edges, or were elevated from their 

 horizontal position. The same igneous influence 

 which hardened the clay into flinty slate, apjjears 

 also to have produced a sublimation of Iron 

 Pyrites, or ot Sulphur, which, combining with the 

 iron in tire clay, formed Bi-sulphnret of Iron, a 

 mineral abounding in the flinty slate. Another 

 change is also observed in the flinty slate rocks 

 near the rail-road cutting in the vicinity of Ports- 

 mouth. The rock is there filled with an infinity 

 of reticulated veins of carbonate of lime. Tliis 

 crystaline carbonate of lime may have been jiro- 

 duced by the fusion of calcareous matter con- 

 tained in the clay by the action of heat, given out 

 dining the eruption of molten rocks protruded 

 from below ; such a theoiy of its formation being 

 supported by the results of artificial experiments, 

 and by observations made at many other places, 

 where such an influence is known to have been 

 exerted. 



Iron Pyrites abounds at the localities above de- 

 scribed, and the facts observed appear to give 

 support to tlie views which we entertain as to the 

 igneous alteration of the rock. 



Subsequent to the elevation of the strata of 

 flinty slate, numerous eruptions of greenstone 

 trap'i-o'ik took place. Extensive fissures having 

 been formed in tlie rock, the melted trap rose in- 

 to, and filled them entirely. From such causes 

 resulted the large veins or dykes. By observa- 

 tions made on the intersections of these dykes, 

 we are enabled to prove that three or more dis- 

 tinct eru|.tions of this intruded rock took jjlace. 

 Sometimes the older dykes are cut ofl^, but more 

 frequently they were ruptured in their midst, and 

 a newer dyke runs either through the middle of 

 the older dyke, or between it and tlie slate rocks 

 which form its borders. 



Some fine illustrations of the foregoing re- 

 marks may be seen on the sea-coast north of the 

 Little Boar's Head. The dykes at that place va- 

 ry in width from a few inches to ten feet. They 

 generally run in a N. E. and S. W. direction, with 

 some irregid-.rities and zigzags. These etii])tions 

 have evidently taken place there, nearly in the 

 same line of direction. The more recent dykes, 

 included in, or collateral with, the older ones, are 

 of a much darker hue, and more compact in tex- 

 ture. The smaller dykes are imperfectly colum- 

 nar in a direction at right angles with the rock in 

 which tlii-y are included, this structure depend- 

 ing on the surfaces where the cooling commen- 

 ced. Huge masses of trap rock, which cooled 

 from the upper surface, are generally colmnnar in 

 a vertical direction, as may be observed in Nova 

 Scotia, on the Eastern coast of Maine, at Mount 

 Holyoke in Massachusetts, and the Palisadoes on 

 the Hudson river, in New York. 



The observer will also remark at the locality 

 near Portsmouth, that the strata of flinty slate are 

 nuich contorted, and that this contortion took 

 place evidently anterior to the eruption of the trap 

 dykes. He will also notice numerous veins of 

 compact felspar in the flinty slate, which probably 



were formed at the epoch of the elevation of the 

 granite rocks. 



The flmty slate occurs also in the town of 

 Portsmo<«h, and along the banks of the Piscata- 

 qua river, where the strata are much broken, the 

 joints being generally in directions parallel to 

 those of a rhombic prism. Oa the margin of 

 the river, near the estate of Col. Ichabod Bart- 

 lett, the slate is divided into such rhomboidal 

 masses, and is torn asunder during winter by the 

 action of freezing water, and produces loose 

 shingle of slate, which pave the shores of the 

 stream. 



The flinty slate region of Portsmouth is sur- 

 rounded by granite rocks, which, in numerous 

 places, have been erupted so as to isolate portions 

 of the slat€, by intrusion between their masses. 

 Such phenomena would give to a casual observer 

 the idea that the slates and granite alt«rnate with 

 each other. 



It will be found, on further observation, that 

 such is not the case, for the ])rimary rocks have 

 merely been forced in between portions of the 

 slate. On our way from Portsmouth to the Boar's 

 Head and Hampton Beach, we had occasion to 

 observe phenomena of the kind above referred 

 to, in the town of Rye. The locality is at the 

 corner of the old road to Portsmouth and the La 

 Fayette road, near the house of Mr. Samuel Lang- 

 don, 1 1-2 miles from Portsmouth. A mass of 

 granite has there been intruded through the slate, 

 and occupies a considerable area, beyond which 

 the flinty slate again appears, and then gives way 

 to a regular granite and gneiss formation, which 

 extends through a large portion of the town of 

 Rye. 



In Portsmouth the intrusion of granite veins 

 and trap dykes into the flinty slate, may be seen 

 in Shoar's woods. The trap dykes pursue a 

 north-east and south-west direction, and are ir- 

 regularly columnar in a vertical direction. 



Breakfast Hill is composed of granite and gneiss 

 rocks, and will furnish an abundance of building 

 stone. The strata of gneiss run N. 16 deg. E., S. 

 IG deg. W., and dip N. 74 deg. W., at an angle of 

 70 deg. from the horizon. 



It will be seen that the flinty slate region in 

 Maine and around Portsmouth is bordered by 

 primary rocks, and to their influence we have, as 

 before stated, ascribed the metamorphoses which 

 the slate has undergone. The clay forming the 

 basis of the slate may have been produced by al- 

 luvial deposits of the fine particles of older gran- 

 ite rocks, and the fineness of the particles shew 

 that it was deposited by tranquil waters in a vei-y 

 gradual manner. 



GRANITE QUARRY IN RVE. 



In "the town of Rye, about a quarter of a mile 

 S. W. from the meeting-house, in the midst of a 

 white-pine grove, a quarry has been opened for 

 obtaining granite, which is a light colored variety, 

 of good texture, and splits tolerably into the forms 

 desired for building stones. 



An abundant supply may be obtained, and the 

 locality will prove valuable, it being in the vicin- 

 ity of Portsmouth. 



From the Farmer's Cabinet. 

 Cob Ileal. 

 Mr. Editor.— On a late visit to a friend I saw 

 in his barn about two hundred bushels of cobs of 

 corn ! How long will it be before we are brought 

 to understand "the nature of things, and perceive 

 their fitness ?" Here we are, giving our stock 

 clean corn meal mixed with wheat bran, and 

 throwing aside the cobs for fiiel, or for nothing, 

 although they have been found of three or four 

 limes the value of bran, for the puri)Ose of nnx- 

 ing with the meal ; a perfectly natural mixture, 

 made without extra labor, or expense, adding 

 about one half to the quantity of our means of 

 feeding, saving the labor of shelling, and the cost 

 of bran ! the cob being suitable as food for hogs, 

 as for any other species of stock, and even for 

 poultry. And when the importance of cooking 

 food for our animals is as universsUy practised 

 as cooking for ourselves, we shall find that there 

 are many ways in which a farmer can make up 

 the deficiency in the state of the markets— with- 

 out going back to the burning of pine knots to 

 to save candles !— Suppose each bushel of ground 

 corn-cobs to be worth but 12;^ cents, what an ad- 

 dition will they prove to the fodder of our corn- 

 crop, and our resources in a long and trying win- 

 ter! Many farmers grow six or eight hundred 



bushels of corn, and supposing that the cob is 

 equal in bulk to half that quantity, here are no 

 less than three oi- four hundred bushels of fod- 

 der additional, procured without labor or expense 

 of any kind, save only the very small charge for 

 grinding. Every mill should be furnished with 

 the means of grinding the cob with the corn, and 

 the saving to be derived from feeding these, and 

 the addition to tlje dung-hill, would form an item 

 in our accounts of considerable moment in these 

 hard times. Is it not a little strange that so small 

 account is taken of the means which are so im- 

 mediately in our power to add to our resources ? 



J. A. 



From the Albany Cultivator. 

 Artificial wateriag places. 



Messrs. Editors of the Cullivator.— Mr. William 

 Robertson of Fishkill Landing, Dutchess Coun- 

 ty, one of our most successful farmers, has com- 

 municated to me the following mode, successful- 

 ly practised by himself, of supplying with water, 

 fields destitute of springs, ponds or rivulets. — The 

 fiirm lately occupied by hin>is now in the hands 

 of its proprietor, J. D. L. Verplank, Esq., where 

 the watering jjlaces constructed by Mr. R., may 

 still be seen. The situation of the farm is upon 

 the whole favorable for the purpose, and the plan 

 therefore may seem to require further tests by ex- 

 periment, before it can be considered invariably 

 successfuL He says it was an entirely acciden- 

 tal discovei-y, — he one morning found one of his 

 calves drowned in a barrel sunk in the usual way 

 for the purpose of collecting water from a spring. 

 The water had sunk to near the bottom of the 

 barrel, and the animal in reaching down for it 

 had lost its balance, and falling, was unable to 

 extricate itself. Vexed at his loss, he immediate- 

 ly ordered the cavity to be filled up; this was ac- 

 cordingly done by throwing in a parcel of round 

 pebble stones, which were lying near at hand. — 

 The next day in passing by, he saw to hia sur- 

 prise, that the water had risen over the tops of 

 the stones, although no rain had fallen, and the 

 season had been very dry. 



The idea then struck him (manifestly errone- 

 ous, as the barrel is not water tight in these ca- 

 ses) that it was similar to the raising of water in 

 a pitcher by throwing in pebbles, and he deter- 

 mined to make the experiment more complete. 

 Accordingly the barrel was taken out and the 

 hole deepened with very little appearance of wa- 

 ter, and he struck his crow-bar down so as to 

 make several deep holes, he then replaced the 

 barrel, packing it well around with earth, and af- 

 terwards filled in the barrel a.s before with the 

 pebbles. In a short time he had the pleasure to 

 find the water oozing in and gradually rising o- 

 ver the stones until it stood permanently some 

 inches over the surrounding level. He repeated 

 the trial in several other fields, and always with 

 success, even in places where, on first digging 

 down, there was not the least appearance of 

 moisture, much less of water ; he considered that 

 the appearance of springiness is of no conse- 

 quence, but that water will at length show itself 

 in the barrel in all cases, and will finally rise 

 eighteen or twenty inches above the surface, ap- 

 parently increasing in quantity for a year or 

 two. 



Such is Mr. Robinson's statement, and he is 

 fidly entitled to our confidence, yet I do not be- 

 lieve that this is an infallible method of obtain- 

 ing water in every situation, strata or soil ; it nev- 

 ertheless appears to me reasonable to suppose 

 that it may prove of great service in many places 

 at present destitute of water, without resorting 

 to expensive boring, digging wells or making ar- 

 tificial ponds ; the last especially from the sever- 

 ity of our seasons, requiring great labor and care 

 in their construction to prevent their being sfiec- 

 ted by frosts or drought. 



I do not know whether the following sugges- 

 tions will throw any light on the rationale of this 

 simple process, which at first sight appears 

 scarcely entitled to notice. The driest soil (to 

 appearance completely dessicated) nevertheless 

 contains some moisture, quickly attracts more 

 from the atmosphere, and, if collected, from a 

 large body of earth, it would form a considera- 

 ble rill. If we sujipose one drop gradually to 

 distil and roll over into the excavation, its fall 

 and its attraction will put in motion the next par- 

 ticle and the next ; and so on as long as there are 

 particles to be affected, and this takes place no; 



