NOTES O'N THE lOTANY CF LXPERIMENTAI. GIUS9-FL0TS. 299 



:notes on the bota:ny of the experimental grass- 

 plots IN ROTHAMSTED PARK, HERTS. 

 By "W. B. Hemslet. 



SlosT English botanists are aetiuaintecl with the extensive series 

 of experiments which Mr. Lawes, assisted by Dr. Gilbert, has been 

 conducting on his estate at Rothamsted for upwards of thirty years. 

 Independently of their value in practical agriculture, these experi- 

 ments possess great interest for the student of botany, whether syste- 

 matist or physiologist. Indeed, it would be difficult to overestimate 

 their value. Besides these experiments in the open fields, it is only 

 necessary to mention the results of the laboratory work, published 

 under the titles, " On the Sources of the Nitrogen of Vegetation ; with 

 special reference to the question whether plants assimilate free or 

 uncombined Nitrogen,"* and a " Report upon some Experiments 

 undertaken at the suggestion of Professor Lindley to ascertain the 

 comparative Evaporating Properties of evergreen and deciduous 

 Trees, "f to show the importance of the labours so patiently and per- 

 severingly continued at an immense outlay, and during a period when 

 comparatively few scientific men, in this country at least, took any 

 real interest in the issues. Even now it is doubtful whether Mr. 

 Lawes receives that sympathetic support which is due to him and his 

 coadjutors for their contributions to scieLce. The greatest reward a 

 man can enjoy, however, is the satisfaction he feels at having discovered 

 a new fact ; and a proof of Mr. Lawes's earnestness in his investiga- 

 tions is found in the provision he has made for the continuation of this 

 experimental research after his death. Many of the field experiments 

 were originally instituted to ascertain in what form certain essential 

 elements in the food of plants could be most advantageously applied. 

 That is to say, in such a form that plants could assimilate them, and 

 at an outlay that would prove profitable to the farmer. 



It is not the purpose of the present writer to enter into these 

 questions in detail here, but rather to point out some of the features 

 of one particular set of experiments which specially come within the 

 domain of what may be termed the biological botanist. 



For a number of years many of the experiments at Rothamsted, 

 notably those on the herbage of permanent meadow land, which alone 

 ■will be considered here, have been carried on for purely scientific pur- 

 poses. As in all investigations, the results of which have not been 

 reduced to plain facts, some little time and patience are necessary to 

 obtain a grasp of the subject, especially as the questions at issue are 

 numerous. There are some twenty variations ot what may be termed 

 the same experiment ; but in order to appreciate their full significance 

 it is only necessary to bear in mind that the investigations, so far aS' 

 the nutrition of the plant are concerned, are limited to the presentation, 



(1861) 



* Philosophical Transactions, part ii., 1861. 



t Journal of the Horlicultural Society of London, vol. vi , parts 3 and 1 



