202 SCIENCE IK SHORT CHAPTERS. 



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reduced in quantity, and the remaining ashes supply the surface 

 of the bog on which they rest with the non-volatile salts that 

 originally existed in the burned portions of the bog. In other 

 words, they concentrate in a small space the salts that were 

 formerly distributed too sparsely through the whole of the turf 

 which was binned. 



As there are great differences in the composition of different 

 bogs, especially in this matter of mineral ash, it is evident that 

 the success of this method must be very variable, according to 

 the locality. 



On discussing this method with Mr. MacAlister (Mr. Henry's 

 steward, under whose superintendence these reclamation works 

 are carried out), he informed me that the bogs on the Kylemore 

 estate yield a very small amount of ash a mere impalpable 

 powder that a light breath might blow away ; that it was prac- 

 tically valueless, excepting from the turf taken at nearly the 

 base of the bog. The ash I examined where the bog burning 

 is extensively practised in Donegal Avas quite different from 

 this. The quantity was far greater, and its substance more 

 granular and gritty. It, in fact, formed an important stratum 

 when spread over the surface of the ridges. These differences 

 of composition may account for the differences of opinion and 

 practice which prevail in different districts. It affords a far 

 more rational explanation than the assumption that all such 

 contradictions arise from local stupidities. 



There is one evil, however, which is common to all bog- 

 burning as compared with liming it must waste the ammonia- 

 cal salts, as they are volatile, and are driven away into the air 

 by the heat of combustion. Somebody may get them when 

 the rain washes them down to the earth's surface again ; but 

 the burner himself obtains a very small share in this way. 



We may therefore conclude that where lime is near at hand, 

 bog-burning is a rude and wasteful, a viciously indolent mode 

 of reclamation. It is only desirable where limestone is so dis- 

 tant that the expense of carriage renders lime practically un- 

 attainable, and where the bog itself is rich in mineral matter, 

 and so deep and distant from a fuel demand that it may be 

 burned to waste without any practical sacrifice. Under such 

 conditions it may be better to burn the bog than leave it in 

 hopeless and worthless desolation. 



I cannot conclude without again adverting to the importance 

 of this subject, and affirming with the utmost emphasis, that 

 1he true Irish patriot is not the political orator, but he who by 



