306 Annual Report for 1908 of the- Consulting Chemist. 
2. Magnesia in Soils. 
My attention has of late years been directed considerably 
to the question of the influence which magnesia exerts as a 
constituent of the soil and when applied to crops. Experiments 
on this point have been carried out at the Woburn Pot Culture 
Station, and with very striking results. These are now being 
extended to the field cultivation. The general bearing of the 
work, so far, has been to show that when the amount of 
magnesia in the land preponderates over that of the lime 
present, a deteriorating effect is produced on the crop. For 
some years past I have noted the results obtained in analysis 
of soils where this fact has been brought out, and have made 
inquiries regarding the cropping powers of these soils. It has 
been brought home to me forcibly, in consequence of these 
observations, that, in cases where complaint has been made 
that the soils do not crop satisfactorily, while there has been 
no evidence of the absence in sufficiency of such necessary 
constituents as phosphoric acid, potash, nitrogen, &c., or even 
of lime, there has been found a marked preponderance of 
magnesia over lime present. To this fact, therefore, I am 
inclined to attribute the failure of the soils to crop properly. 
Such an instance is the following, the soil coming from near 
Burton-on-Trent. 
(Soil dried at 212° F.) 
Organic matter and loss on heating . 
5-18 
Oxide of Iron ...... 
283 
Alumina ....... 
4-07 
Lime ....... 
•63 
Magnesia ....... 
1-44 
Potash ....... 
•74 
Soda ....... 
•28 
Phosphoric acid ..... 
•15 
Sulphuric acid ...... 
■01 
Insoluble silicates and sand 
84-67 
100-00 
Containing nitrogen ..... 
•146 
This soil, one would say generally, showed no deficiency 
in either vegetable matter, nitrogen, phosphoric acid, potash, 
or lime, and yet the evidence of the farmer went to show that 
it would not grow satisfactory crops. It will be noticed that 
the magnesia was largely in excess of the lime present, being 
more than double the latter, and to this fact I am inclined to 
attribute the failure of the land. This is but one of several 
similar instances which I have collected, all bearing on the 
same point, and confirming the work at Woburn to the effect 
that predominance of magnesia over lime is an undesirable 
