552 THE SOUTHERN PLANTER. [September 



of advice is apt to strengthen its opposition. 

 But the activity of this quality, unre- 

 strained by the fear of degradation, and ex- 

 cited by the hope of applause, may be en- 

 listed through the pi ess, and become highly 

 useful in the improvement of Agriculture. 

 Whatever it can thence acquire, it will 

 practice as its own, and propagate with zeal; 

 and its great share both of talent and in- 

 dustry, renders it a coadjutor worthy to be 

 conciliated. 



Great social ends are effected by seizing 

 a crisis in public opinion. During the pre- 

 dominance of a temper for emigration, in- 

 flamed by the cheapness and proximity of 

 new land, neither precept nor example could 

 demonstrate the propriety of improving the 

 old, or subvert the ruinous habit of killing, 

 because we could flee from the corpse. But 

 now when this habit is checked by the 

 general appropriation of good new land, by 

 its high price, and by its increasing remote- 

 ness from commerce, the public begins to 

 look for prosperity in the true place, and to 

 disclose some ardor to discover a remedy 

 for an evil, which emigration will soon cease 

 to furnish. As we cannot much longer fly 

 from worn-out lands, and recompense our- 

 selves for unequal laws, by retiring to more 

 fertile regions j we shall soon turn our eyes 

 towards the means by which we may be en- 

 abled to live at home. Let not this new 

 temper stop at hope or evaporate in theory. 

 Let it not be neglected by a Society for pro- 

 moting Agriculture. Enlivened by writing, 

 printing, example and experiment, excited 

 by rewards, and encouraged by political 

 justice, it is able to recover the fertility 

 which has been lost and to prevent the ruin 

 of the State which is impending. Neglected, 

 it will gradually sink into despair, and the 

 favourable moment for effecting an object, 

 filled with gratifications for all classes of 

 society, may possibly be lost forever. 



From the American Farmer. 



Guano versus Coprolites. 



Laboratory of St. John's ColleoxE, } 

 Annapolis, 14th May, 1860. j 



Coprolites are fossil, or petrified excre- 

 ments of turtles and other animals. 



Guano is the excrement of birds, &c. 



Coprolites differ in solubility from guano, 

 although composed of the same elements in 

 the same ^proportions — being more dense, or 

 specifically heavier, and having their parti- 



cles so closely united to each other as to ex- 

 clude solvents except from their outer sur- 

 face. The finest powder that can be pro- 

 duced by mechanical trituration or grinding 

 will not bring coprolites to that atomic state 

 of division which characterizes the phos- 

 phates in guano and bones that have not 

 been petrified or converted into stone. 



There are four phosphatic compounds in- 

 spected and sold as guano in the Baltimore 

 market. 1st. The guano now obtained from 

 the Pacific coast, resembling the Mexican. 

 2d. Guano that has been concentrated by 

 exposure to the weather, still however re- 

 taining its porosity and solubility — such, for 

 instance, as the Nevassa guano. 3d. Guano 

 that has undergone certain changes which 

 have, in a remarkable degree, improved its 

 solubility and value by the interposition of 

 sulphate of lime (gypsum) between its par- 

 ticles j the American guano represents this 

 class. 4th. Coprolites, or fossil phosphates, 

 that are now sold under the name of guano, 

 and used extensively for making manipu- 

 lated guano, as a substitute for the genuine 

 article above described. In England, cop- 

 rolites are ground and mingled with oil of 

 vitriol, in order to increase their solubility • 

 but even under these circumstances they 

 are not as valuable as guano or bones simi- 

 larly treated, for the reason above stated, 

 viz : because each particle is compact and 

 solid, while guano is full of pores, however 

 small the particles. It must be manifest, 

 then, that manipulated guano made with 

 coprolites is not as valuable to the farmer as 

 that made with guano. 



I wish to call the attention of the agri- 

 cultural community to this fact, and caution 

 them against purchasing coprolites, that are 

 now ground and sold as guano or " manipu- 

 lated guano." Any novice orryro in chem- 

 istry can make an estimate of the compara- 

 tive solubility of the articles referred to. 

 For instance, take £ oz. of the coarse Ne- 

 vassa guano before it is ground, and com- 

 pare it with the same weight of the fine 

 powder that is sold as guano, and vaunted 

 as the best in the market; throw each sam- 

 ple on a small filter suspended in a wine- 

 glass, that has been about half filled with 

 nitric acid, diluted with about nine parts of 

 water. After about two or three hours it 

 will be found that the Nevassa guano is 

 more soluble in the proportion of 5 to 21, 

 viz : the Nevassa guano yields 21 parts of 

 phosphate of lime to cold dilute acid, while 



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