554 



REPORT — 1880. 



magnesia to supply all the wants of wheat, though analysis shows the presence of 

 mere traces of it only, or none at aU. Mr. N. Whiteley, land surveyor, the author 

 of a treatise ' On the application of Geologj' to Agriculture,' whilst recei^-ing as 

 well founded the common prejudice against the magnesian lime in its hot state, 

 does full justice to the fertilising eifects of magnesia in its mild condition. He says, 

 speaking of land near St. Ke^ern, in Cornwall : ' If we seek for a soil theoretically 

 perfect it may be found in this formation. The large amoimt of magnesia which 

 this fruitful soil contains (9 per cent.) is worthy of observation.' Of the magnesian 

 limestone formation he saj^s that ' much of it is thin, light, and dry,' and ' we are 

 prepared therefore to meet with a soil of medium quality ; miich of the soil on the 

 magnesian limestone is in arable culture, but from Standrop to Darlington the soil 

 may be considered the best and richest grazing land in the North.' Strong con- 

 firmation of the views I am seeking to establish is to be derived from a considera- 

 tion of the cases of soils, which are either abmidantly supplied with, or are very 

 deficient in magnesia. 



In the following table are given the proportions of lime and magnesia found in 

 both fertile and barren soils. 1 give the lime as well as the magnesia, because that 

 substance is considered, very lightly, a most important ingredient of manures, 

 although usually its proportion in soils is considerably in excess of the magnesia: — 



Propoktion of Lime and Magnesia in 1000 parts op Very Fertile and 



Fertile Soils. 



No. 1 is from the analysis of the celebrated black earth of Russia. This remark- 

 able soil is ' the finest in Russia, whether for the production of wheat or grass.' It 

 nourishes, on 60,000 square geographical miles, a population of more than twenty 

 millions of souls, and yet ' exports upwards of fifty millions of bushels annually.' 

 This very properly stands first in my table, as it contains a very large amount of 

 magnesia, and is the most fertile, probably, of any which the table includes. 



No. 2. From an analysis by Spreugel of the soil of Nebstein, near Olmutz in 

 Bavaria, which had been cropped in 1847 for nearly 160 years successively ' with- 

 out either manure or naked fallow.' 



No. 3. By Boussingault, a soil from Calvario near Tacunga, Ecuador, South 

 America. It ' possesses extraordinary fertility.' 



No. 4. ' A very fertile allu\-ial soil from Ilonighpolder,' analysed by Sprengel ; 

 no manure has ever been applied to it. The subsoil contains to a great depth the 

 same composition as the surface soil. 



No. 5. Soil from Midlothian, analysed by Br. Anderson. It produces excellent 

 wheat.' 



No. 6. From an analysis by Sprengel of a very fertile alluvial soil in East 

 Friesland formerly overflowed, but which had been in 1863 cultivated for sixty 

 years with corn and pulse crops without manure. 



Nos. 7, 8, 9, 10. From soils at Gottingen, from near Hanover, from Alt-Arenberg 

 in Belgium, and from a Adi'gin soil on the banks of the Ohio respectively. The 

 analyses are by Sprengel. 



I do not, of course, assume that the fertility of these soils is due entirely or 

 chiefly to the magnesia they contain ; the black earth of Russia, for instance, 

 contains also more than 2 per cent, of nitrogen ; nor do I suppose that in very 

 many cases the addition of magnesia where the proportion of it is less, cannot be 

 dispensed with ; but I do saj', seeing the disastrous eflects which accompany its 

 absence, as shown by Ville, the question merits the serious attention of agriculturists. 

 This -will be more apparent from the following table of 



