LIME. 



LIME GRASS. 



day, and require nearly one of coal for every mouths, the stone and coal should be carefully 



two measures of lime burnt. In a country sale measured, so that the workmen can proportion 



of lime, the quantity sold every day is liable to the fuel employed to the quantity of stones, and 



great fluctuations : two or three cart-loads will it is obvious that the quantity of coal to be 



sometimes only be required from an establish- used must depend upon its relative quality and 



ment which, the day before, supplied forty; and the hardness of the stone to be burnt. If this 



as lime is known to be a commodity, when ex- measure was adapted to kilns of any con- 



posed to the action of air, which becomes more 

 bulky and heavy, and in that stale does not ad 

 mit of being carried to a distance without addi 



struction, the lime snells would be found better 



burnt. 



" Circular kilns are constructed with similar 



tional labour, it has been an object of import- eyes or openings at the bottom, and not more 

 ance with me to find out a construction of a kiln than 8 feet wide at 18 'feet from the base, and 

 which will allow of lime being kept for several contracted to 4 or 5 feet wide at top. In light- 

 days without slaking, and at the same time to ing the kiln at the commencement of burning, 

 prevent the fire escaping at the top of the kiln, | some care should be taken not to allow the fire 

 if the kiln stands 24 hours without being em- ! to remain below the upper grate. There are 



ployed, especially during the autumn and win- 

 ter, when the air is cold and the nights long. 

 I now employ kilns of an egg shape, and also 

 oval ; the oval-shaped kilns are divided by 



two iron grates at the bottom of the kiln : the 

 upper grate consists of iron bars 8 or 10 inches 

 distant from each other across the kiln, be- 

 tween which the pieces of burnt lime fall down 



arches across the kiln, descending 4 feet from j upon a lower grate with iron bars one inch 

 the top; the object of the arches across the from each other, which allows the lime ashes 

 kiln is to prevent the sides of the kiln falling to fall through them into an ash pit ; these 

 in or contracting, and also to enable you to lime ashes are found very useful as a top- 

 form circular openings for feeding in the stone dressing for grass ground, and are a clear gain 

 and coal at the mouth of the kiln ; upon this to the proprietor of lime-kilns for public sale, 

 plan, a kiln of any length might be construct- 1 As a burner of lime for agriculture in an ex- 

 ed with numerous round mouths. In the model | tensive district of country to the extent of 



150,000 imperial bushels annually, the value 

 of the lime ashes which fall through the lower 

 grate amounts to more than 150/. annually; 

 the lower grate is 3 feet above the ground, and 

 the upper grate is the same distance from the 

 lower one. The kilns I employ at Closeburn 

 are upwards of 30 feet high, and nearly per- 

 pendicular, which is the cause of the great 

 heat in this construction of kiln, and which is 

 found to burn lime more equally than circular 

 kilns of large dimensions. (Trans. High. Soc. 

 vol. ii. p. 127.) 



The limestone quarries of Scotland are de- 

 scribed by Mr. Carmichael (Ibid. vol. v. p. 57) : 

 he observes, when speaking of the uses of this 

 valuable earth, " how sterile must have been 

 the soil, how cheerless the dwellings, and how 

 scanty the resources of Britain before lime 

 came into general use." And on the method 

 of calcining limestone in some of the limestone 

 quarries in Scotland there is a paper. (Ibid. 

 p. 441.) 



is a saving of eight-twentieths of the weight; and I Limestone Gravel. There are some traces of 

 I find that an equal measure of coal and coke this manure in the Isle of Anglesea; but in ge- 

 furnish the same quantity of heat in burning neral, it is seen in quantities only in Ireland, 



where it is very common. It is in appearance 

 only common gravel, of a blue colour, mixed 

 with stones as large as a man's fist, and also 

 with loam or clay : it has a strong effervescence 

 with acids, and, when used, is attended with the 

 usual effects of marl or lime. For bogs, it ex- 

 ceeds every other manure, as its weight assists 



of the kiln sent to the Highland Society, Book- 

 er's conical cover may be seen revolving upon 

 an iron ring placed upon the circular mouth, 

 and having placed a lid to the cover, I am en- 

 abled to prevent the escape oflheat at the top, 

 and by cast-iron doors at the bottom the air is 

 prevented passing through the kiln ; so that, 

 by these precautions, the lime burner can regu- 

 late the heat, and prevent its escape for several 

 days, when the fire would be extinguished at 

 this season in the course of 24 hours. This is 

 an object of great importance, as it enables the 

 lime to be burnt as well, and with as small a 

 quantity of fuel in the winter as the summer 

 season, and to supply the farmer with as well 

 burned lime, and at any time of the year, which 

 cannot be done in the common construction of 

 kilns, open both at top and bottom, for the rea- 

 sons I have before stated. From the great ex- 

 pense attending the driving of fuel from a dis- 

 tance of 25 miles from my own coal-pits, I have 

 adopted the practice of coking the coal, which 



lime, which is somewhat paradoxical, but not 

 the less true. The coal is found to have little 

 effect upon the stone till it is deprived of its 

 bitumen, or is coked in the kiln ; for, during the 

 time the smoke is emitted from the top of a 

 lime kiln, little or no heat is evolved. A kiln 

 in which coke is the fuel employed, will yield 

 near a third more lime shells in a given time 



in the improvement of that loose and spongy 



than when coal is the fuel ; so that coke may I soil. Upo'n strong clays, the use of it is" unri- 

 be used occasionally when a greater quantity vailed, for it has all the effect of a dressing of 

 of lime is required in a certain time than usual, lime, and gives friability yet more than chalk 

 as it is well known to lime burners that the does. It destroys moss infallibly. Upon what- 

 process of burning is done most economically ever soil it is used, it is found very durable, 

 when the kiln is in full action, so as almost lasting, in many instances, in great heart, from, 

 constantly to have a column of fire from the twenty to forty years. In limestone counties, 

 bottom to the top of the kiln, with as short in- | all blue gravels should be examined; for it is 

 tervals as possible in working the kiln. an invaluable treasure, wherever found. 



" In working a kiin with narrow circular LIME or LYME GRASS. See ELYMTJS. 



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