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THE FARMER'S MAGAZINE. 



watched night and da}'. He further remarks that in 

 other countries, where this practice was prevalent, and 

 especially in Piedmont, clods of clay are mixed with the 

 turf. He argues at some length the policy of having one 

 or two large heaps, or else a numerous series of small ones ; 

 and although the large heaps offer some advantages, the 

 ciiief of which is the economy of fuel, he prefers the smaller 

 ones, as being more handy for spreading, and also because a 

 greater area of surface is burnt by the multiplicity of the 

 heaps over the land, and especially, he adds, because the 

 earth is not baked so hard as would be the case with a large 

 heap, where the earth in immediate contact with the fire 

 would be overburnt, and produce no good effect. After 

 considering all these points, the author goes on : 



" As soon as the fire is extinguished, the earth will cool 

 of its own accord in a short time, and it will remain in 

 heap until a fall of rain is anticipated, when it should be 

 spread evenly over all the surface, except over the spot 

 where the heaps stood, because there the earth is suffi- 

 ciently burnt and prepared ; this will appear evident from 

 the wheat, in its time, being more luxuriant in those places 

 than elsewhere, as if in those places alone the richest 

 manure had been applied. 



" After this, the field should be ploughed, but very lightly, 

 at most three inches deep, in order to mix by little and 

 little the burnt with the raw soil of the bottom. The sub- 

 sequent ploughings should be deeper ; and if the burning 

 has been expedited in June, and good showers have 

 occurred, canaryseed, turnips, &c., either mixed or separate, 

 can be sown ; then in the following October rye or wheat 

 can be sown, three or four years in succession." 



Further, the author says : " Not only will such earth, 

 burnt and thus prepared, enrich the land, but if carted to 

 other fields, as is done with stable-dung, it will greatly 

 amend them also. All kinds of fruit trees are rejoiced by 

 this earth, if some of it is put around their roots ; and it 

 will also be highly beneficial to artichokes, asparagus, and 

 other precious garden plants." 



Then meeting the objection of those who think this 

 amendment of the soil is not a lasting one, thinking all the 

 fertilizing elements are destroyed by the action of the fire, 

 he says : " As to the fear of short duration, those alone 

 who have not tried it have this opinion, doubting a thing 

 so well authenticate i; for every tillage thus prepared 

 remains strong and vigorous eaough to serve as long as can 

 be desired, provided the field be treated as to rotation of 

 crops according to the laws of good husbandry, and not 

 according to the ancient oracle, 'Do not draw all the 

 nutriment from thy field.' All these things weighed and 

 considered, our husbandman shall prefer this mode to any 

 other, if the high price of fuel does not hinder him ; and 

 this is the only excu:e he can have. And, as a conclusion, 

 he will form his opinion of this practice from the report of 

 those who use it the most, and who say in their patois : 



' Those who do not pare and burn, 

 AVhen others reap, will only glean.' " * 



Such were the ideas about paring and burning three hun- 

 dred years ago, when a timc-hallowed experience was the 

 only guide of agriculture. Those who have had the good 

 fortune of reading Dr. Voelcker's able paper upon this sub- 

 ject will not fail to be struck with the great analogy exist- 

 ing between his statements and those of Olivier de Serres ; 

 the only difference, a very striking one, showing the ira- 



* Qui non crfeme, ou non f6me, 

 Quan tous autres moissonnou, il glene. 



meuse stride accomplished by science during this long 

 interval, is, that Olivier de Serres gives no other reason for 

 recommending the practice than the experience of ages, cor- 

 roborated by his own ; whilst to this cogent one, Professor 

 Voelcker adds the forcible arguments of scientific analysis 

 and demonstration. 



I will now submit to the reader the result of my investi- 

 gation in Dauphinc, where, as I have stated, the practice of 

 paring and burning exists as a regular and well-established 

 mode of manuring the land at a small cost. 



The beautiful plain of Graisivaudan, so well known for its 

 picturesque magnificence audits extraordinary fertility, forms 

 the basin of the river Isere, from the frontiers of Savoie, to 

 the city of Grenoble. Below Grenoble, following tte 

 course of the river, it takes the name of Moirans, up to the 

 Rhone, iu which the Iscre falls. On one side of the valley 

 is the chain of the Alps ; on the other, the group of the 

 Chartreuse mountains. Its soil consists of alluvial deposits 

 from the disintegration of the calcareous rocks of the neigh- 

 bouring mountains brought down by the river Isere, subject 

 to frequent overflowings, and by the torrents from both 

 sides of the mountain boundaries, which from every ravine 

 pour into the valley, along with their turgid waters, 

 streams of calcareous gravel, loosened from the limestone 

 cliffs by the action of the atmosphere, and then borne 

 along by the torrents. Such soil like that described by 

 Dr. Voelcker in the neighbourhood of Cirencester is then 

 eminently calcareous, the proportion of carbonate of lime 

 being generally from 30 to 40 per cent., and sometimes 

 amounts to 50 and 55 per cent. To this is not confined the 

 remarkable analogy existing between these soils, both so 

 greatly benefited by the same operation : the proportion of 

 nsoluble silicates is nearly the same in both ; and this is 

 an important feature, as I will presently explain. 



The mode of paring and burning in the Graisivaudan Valley 

 is identically the same as that described by Olivier de Serres : 

 the turf is pared, dried, and then formed into small heaps over 

 a faggot. The number of these heaps would amount to about 

 350 per English acre. As it is recommended by Olivier de 

 Serres, the great point of the operation is to produce carboui- 

 zatioD, and not incineration, of the superincumbent vegetable 

 and earthy matters. But however carefully the ovens are 

 watched, there is always a certain degree of incineration, in 

 the centre of the heap, of those parts which are inclose prox- 

 imity to the fire ; the earthy matter becomes bricky, and of a 

 reddish colour. This, in the experience of the most skilful 

 burners, is to be avoided. 



M. Emile Gueymard, a government chief engineer, who has 

 paid great attention to this subject, points also to theoverburn- 

 ing of the earthy and vegetable matter as an evil by all means 

 to be avoided. This eminent chemist very truly says that the 

 turf and the clods contaiu humus, and other matters, which, 

 during the burning process, yield some carbonate of ammonia. 

 It is, then, very evident that, if the temperature be too high, 

 all the humus disappears, and the carbonate of ammouia — a 

 most valuable fertilizing element — is volatized and totally 

 escapes. 



Besides the mechauical advantages of paring and burning, 

 which everyone will admit, for strong retentive soils, and those 

 others so ably demonstrated by Dr. Voelcker as resulting from 

 that practice upon the poor clay lands of the Cotswolds, there is 

 another upon which M. Gueymard lays a great stress, that is the 

 transformation of insoluble silicates into gelatinous or soluble 

 silicate immediately available to the plants. The stems of most 

 herbaceous plants contain from 30 to 50 per cent, of silica, 

 giving them that rigidity which enables them to withstan 



