238 



J. B. LA WES AND JUSTUS TON LIKBIG. 



in August Last year, near this city, we saw many 

 good crops that were not sown till the last week in 

 August. A clean, sandy, or even mucky soil is well 

 sailed for turnips, and it cannot be made too fine and 

 light by plowing, harrowing, etc. A pound of seed 

 per acre, sown broadcast, will, in a fair season, aflford 

 plants enough, even after the " fly " has decimated 

 them. If too thick, a harrow can be run over the 

 field to thin them, or, what is better, they can be 

 eingled out a foot apart with the hoe. "We really 

 can see no reason why every farmer can not in this 

 way BOW several acres of turnips. It must- be an 

 uncommonly poor season if a sufficient crop is not 

 obtahicd to pay for the labor and e.xpeuse. We feel 

 confident that such a practice will prove profitable, 

 even though nothing more is done with the turnips 

 thou to consume them on the land with sheep late in 

 the fall, when grass begins to fail. 



J. B. LA WES AND JUSTUS VON UEBIG. 



LiEBia, on the point of editing a new edition of 

 his " Uhemistry in its Application to Agriculture and 

 Physiology," has had occasion, as he tells us, to ex- 

 amine the agricultural journals, in order to acquaint 

 himself with the results of practical experience that 

 have been published since the appearance of the 

 last edition of his book, in 1815. The result of this 

 examination has led to the simultaneous publication 

 Id G^rmiiny, England, and the United States of a 

 pamphlet entitled "The Relations of Chemistry to 

 Agriculture, and the Agricultural Experiments of 

 Mr. J. B. Lawes." The object of the pamphlet we 

 will allow LiEEiG to state in his own words: — "The 

 ■experiments of Lawes, of Rothamsted, are distin- 

 guished above all others by their extent and duration; 

 and since the conclusions that their author has de- 

 duced from them stand in contradiction to the prin- 

 ciples which I have taught in the above work, I con- 

 eider his so-called practical criticism of scientific 

 views especially adapted to serve as an example to 

 convince agriculturists how uecessaiy it is to select a 

 correct method of cxpeiimenting, when, thereby, an 

 opinion or doctrine is to be confirmed or refuted." 



"All the experiments of Lawes prove precisely the 

 contrary of that which, in his opinion, they should 

 prove. 1 consider them, indeed, as the firmest sup- 

 port of the theory which they were originally in- 

 tended to combat, and the facts which he has ascer- 

 tained, teach so many important doctrines in refer- 

 ence to the cultivation and manuring of the soil, 

 that I hold them to be of very special value to the 

 theory of agriculture." 



Lawes' experiments are " the firmest support " of 

 the " principles taught " by Liebio, and are of " very 

 special value to the theory of agriculture," and caW 

 eulated to teach " many important doctrines in refer- 

 ence to the cultivation and manuring of the soil." 

 What, then, are the principles taught by Liebiu, aod 

 what tre the results of Lawes' experiments? 



It Is by no means easy to answer the first (jnestion. 

 An eminent German philosopher has said that Lib- 

 big's writings "swarm with contradictions;" and Dr. 

 iltjoo Mom, characterises his style as one " which 

 leaves the reader, on almost every important topic, 

 in perfect uncertainty what it really is that Liebio 

 means." 



The principal point of difference between Lawes 

 and Liebio is in regard to the so-called " mineral 

 theory" whirli Mr. Lawes thought embodied in the 

 following sfntence in Liebio's " Chemistiy in its Ap- 

 plication to Agi-iculture and Physiology : " " The 

 crops on a field diminish or increase in exact propor- 

 tion to the diminution or increase of the mineral sub- 

 stances conveyed to it in manure." Liebis says Mr. 

 Lawes appears to be unacquainted with any other 

 sentence in his book, " and this sentence he has en- 

 tirely misunderstood.' Again he says, " It is impos- 

 sible to believe that he (Mr. Lawes) had any know- 

 ledge of this theory or was acquainted with my doc- 

 trines, otherwise, how could he have declared my 

 opinions to be inconsistent with his experimental re- 

 sults?" Again, " It is not difficult to refute the views 

 of another, if we attribute to him false assertions 

 which he has not made." Again, " That the mineral 

 theory of Liebio is a pure invention of Mr. Lawes' 

 might be clear to every one." Again, " My remark 

 * * cannot be considered incorrect because Mr. 

 Lawes has misunderstood its sense." 



Leaving out of the question the work on " Chem- 

 istry in its Application to Agriculture and Physiolo- 

 gy," in which Liebig now declares he did not teach 

 the " mineral manure theory," let us see what he has 

 written elsewhere, and also what othens, besides Mr. 

 Lawes, have taken to be his meaning. In a letter 

 to the Revue Scicntifique et Industrielle, Liebio 

 says: 



" In a short time I intend publishing a work which, 

 I tru.st, will be interesting in the present state of ag- 

 riculture. Tou are aware of the great importance 

 which theoretical persons attach to the presence of 

 ammonia in manures; so much so, that in France 

 their value is estimated by the quantiiy of azote or 

 ammonia they contain. For myself, for the last three 

 years I have partaken of the common opinion, and 

 regard the azote as not only useful Ijut also necessa- 

 ry; but my last experiments, as well as careful obser- 



