130 



GENESEE FARMER. 



JUNB. 



Agricultural Geology of Onondaga County. 



TiiK second numi)er of the Quiirterly Joumal 

 of Agriculture contains a valuable paper on the 

 Agricultural Geology of Onondaga County from 

 the pen of Prof. Emmons, State Geologist, in 

 which are embodied many original analyses of 

 rocks, soil and waters. As the strata found in 

 Onondaga County extend west to the Niagara 

 river, giving rise to sails of a like character, with 

 slight modifications, the facts set forth by Prof. 

 E. will apply as well to the counties of Cayuga, 

 Wavnc, Monroe, Orleans and Niagara, asta On- 

 ondiiga. Had we room we should copy the arti- 

 cle entire, for we regard it as worth at least five 

 years' subscription to the quarterly, which is but 

 $2 per annum. As it is, we shall draw largely 

 from the Geological and chemical information 

 first given to the public in this paper, and make 

 such comments as will render the subject intelli- 

 gible and interesting to unlearned farmers. For 

 t.he right understanding of this class of our read- 

 ers, it should be stated that all rocks are natural- 

 ly divided into two classes. One class, like hard 

 crystalline granite, was formed by the cooling of 

 melted matter. The distinguishing fact that such 

 rocks have been melted by volcanic or subterra- 

 neous heat has secured to them the appellation of 

 l^nenous Rocks, from 7g7iis, fire. The other 

 class is formed by matter broken into small par- 

 ticles like the dust of the earth, roil, and sediment 

 in water, which being deposited in layers — stra- 

 ta — and then consolidated by immense pressure 

 and chemical affinities, constitute Aqueous Rocks, 

 from aqua, water. The latter class is also termed 

 Sedimentary, from the circumstance of the depos- 

 it of their constituents as sediment at the bottom 

 of oceans, lakes, &c. Most of the rocks in this 

 State are sedimentary — near the centre of which 

 (sujiposing their layers or strata to be spread out 

 over the surface of the State, like the leaves of a 

 book, one upon another,) are the Onondaga rocks. 



The thickness of the sedimentary strata be- 

 low those found in Onondaga county, is about 

 3000 feet; while the thickness of the same class 

 of rocks above the Onondaga strata exceeds that 

 estimate. VVe wish to fix the readers attention 

 on the fact that, the rooks formed by deposits in 

 the bed of an ocean, which once covered, for in- 

 definite ages, this continent, are one mile and a 

 quarter in thickness, according to the Geologi- 

 cal survey, and measurement. • It %vould i)e too 

 great a digression to show how the depth of stra- 

 tafied rocks is measured. 



The rock first described by Prof Emmons is 

 tiie Red Shale, which underlies the whole north- 

 ern border of the county. Its greatest tliickness 

 is 500 feet. It is properly a red marl, of a clayey 

 or argillaceous character, having sandy portions 

 more or less inters])ersed over its surface. The 

 analysesof this rock and of tiie soils formed main- 

 ly of its debris — comminuted fragments — present 

 fiictd of great interpst in practical agriculture. — 



The following table shows the composition of both 

 the sandy and argillaceous portions of the rock r 



Scaidy. Marly. 



Silex, 68.y.5 6iJ.8(J 



IVroxide of Iron and Alumina, C.25 14. 9S 



magnesia, 5.75 0.40 



Cirlionate ofLinie,.. 10.25 9.8<> 



I'iiosijhatf- of Alumina and pbos- 



. pliatc of tlic I'croxiJe of Iron, 00. 00 0.14 



Organic matter, 6.0O 4.50 



Water, 1.00 . 6.45 



90.50 99.25 

 Tlie sandy variety was taken from Canastota, 



in Madison county ; the marly from Kirkville, 



Onondaga county. 



The followmg are the constituents of the soil 



formed of the sandy variety of red shale ; 



Water, 1.5ff 



Organic matter ,^ 2.50 



Silex , - .85.00 



I'eroxide of Iron and AluminQ, &,.12 



(^'arbonaleof Lime, 2.17 



Magnesia, 0.12 



Phosphate of Alumina, 1.00* 



100.41 



The above analyses reveal the curious fact that 

 the native rock contains more than twice as much 

 "organic matter" as the soil — the latter having 

 only "21 per cent., and the former 6 per cent. — - 

 Although the fact is not so stated, it is probable 

 'hat this specimen of soil has been cultivated, and 

 a portion of its organic matter consumed by de- 

 composition and the culture of plants- 



In the rock there is 5.75 per cent of magnesia. 

 In tlie soil only .12 per cen*», or -^-^^ of one per 

 cent. This shows that, as the salts of magnesia 

 are very soluble, they soon disappear, or nearly 

 so, from the surface soil of cultivated fields. In 

 the rock there is over 10 per cent of carbonate 

 of lime. In the soil only 2.17, or one-fourth the- 

 quantity in the parent rock. Lime too, on lime- 

 stone rocks, goes fast. The silex — sand — being 

 insoluble, has increased, relatively,, from 68.25> 

 to 8.5.00 per ce-nt. In our public lectures, and 

 through the columns of this jourrml, we have 

 long endeavored to impress on the minds of far- 

 mers that the soluble alkalies, and the alkaline 

 earths, as well as the organic elements in their 

 soils, are constantly being dissolved and washed 

 away, by rains and sno-ws, into creeks and rivers. 

 Hence, the stirring of the surface of the earth 

 with the plow, harrow and hoe, without cropping,, 

 will exhaust a field of its fertilizing elements. 



Pi-of E. well remarks that this red sliale or 

 inarl may be advantageously used as a top dress- 

 ing, especially for i»nproving^ wheat land.s. It is 

 doubtless to be found in Wayne, Monroe, Or- 

 leans and Niagara counties, although we are not 

 sufficiently acquainted with localities to name 

 them. On the Geological Map of the State, the 

 Onondaga "Salt Group" is laid down as extend- 

 ing in a narrow belt up the valley of the Gene^ 

 see river to Fowlersville, in Livingston county, 

 although r)atavia is some miles south oi' its south- 

 ern line in Genesee county. 



