CONTINENTAL NOTES — GERMANY. 2 I Q 



though not always reliable in his statements regarding the 

 heather regions, found an increasing number of followers who 

 could think of no other reason accounting for the mortality ; and 

 Albert felt thus compelled to make independent researches in 

 this direction. 



He had ascertained by numerous investigations on the various 

 areas, that the porosity of the soils amounted to never less than 

 45 °/„, and that, unless lying within the zone of the natural water 

 level, they cannot permanently retain more than 25 % of water, 

 leaving, even when fully saturated, an open air space of not less 

 than 25 7o- Nowhere did he observe anything in the nature of 

 the surface cover which could successfully resist the energy 

 developed by the diffusion of gases, atmospheric pressure, 

 the changes in temperature, evaporation, etc. Albert foresaw, 

 however, that a further objection might be raised, viz., that in 

 consequence of the stagnation of the air in the soil, it had lost 

 its oxygen, and was solely or at least chiefly composed of 

 nitrogen and carbonic acid gas, and had thereby become inactive 

 and valueless. This objection, if raised, could be met only by 

 direct analytical investigations of the air in the soil. 



The chief, in fact the only real, difficulty connected with this 

 investigation consisted in obtaining air from out of the interior 

 of the soil, which could be guaranteed, and would be accepted 

 as undiluted by the outer atmosphere. After many experiments 

 and trials, Albert invented and constructed an instrument by 

 which this difficult and delicate operation could be, and as 

 a matter of fact was, successfully accomplished. The description 

 of the instrument, its working, and the process of the subsequent 

 analyses, cover nearly six pages of print, and we must content 

 ourselves with the results he obtained. The average of a large 

 number of analyses gave for air in the soil 1979 °/o of oxygen, 

 against 2o'93 % iri the outside air, and 0*246 '^/^ of carbonic acid, 

 against 0-03 % i" the open. 



Albert's concluding investigation took place mainly in the 

 Miinster forest division, where the various methods adopted in 

 the treatment of the very extensive areas afforested with Scots 

 pine afford special object lessons. In addition to some older 

 Scots pine afforestations, which are in a satisfactory condition, 

 there are large areas broken up, during the closing years of 

 last century, to a depth of 50 to 80 cm., by a steam-plough, 

 others, where, at a somewhat later date, the soil was turned 



