GAS-WORKS. 



GAS-WORKS. 



stances. Certain diseases follow the course ! 

 of particular winds ; and the stones or fire- j 

 balls, and similar substances, which have in 

 all ages been seen to fall from the atmosphere, J 

 completely baffle the scientific conjectures of 

 the meteorologist. With such speculations, 

 however, the cultivator need not disturb him- 

 self: resting contented with the knowledge he 

 possesses of the invaluable and essential 

 powers of the known gases and vapour of the 

 atmosphere to assist and sustain the growth of 

 his crops, and adopting in consequence those 

 improved modes of cultivation which that 

 knowledge suggests, he will patiently await the j 

 time when the future discoveries of science i 

 shall still farther enlarge his sphere of useful- j 

 ness, by enabling him to draw forth those 

 latent powers of production which, there is 

 every reason to believe, yet remain hidden in 

 the soil. (Quart. Journ. of Agr. vol. ii. p. 32.) 



Some curious experiments upon the gaset 

 hurtful to i'1-zetation were made by M. Macaire. 

 Some plants of euphorbium, mercury, ground- 

 sel, cabbage, and sowthistle, with their roots, 

 were placed in the morning in a large vase 

 into which chloride of lime had been intro- 

 duced. The roots were then separately soaked, 

 and the quantity of chlorine disengaged was by 

 no means sufficient to destroy the vegetable 

 tissue. At night the plants had not suffered, 

 and the smell of the chlorine was unchanged. 

 The same plants placed in the same vase with- 

 out any addition of chlorine, were found quite 

 faded the next morning, with the exception of 

 the cabbage. The odour of the chlorine had 

 entirely ceased, and had been succeeded by a 

 disagreeable acid smell. The experiment being 

 several times repeated, by rendering the extri- 

 cation of chlorine more considerable, produced 

 the same result, and the plants supports! an 

 atmosphere strongly impregnated with chlorine 

 by day, while a much weaker dose always de- 

 stroyed them during the night. Similar results 

 were obtained when the vapour of nitric acid 

 was employed, nitrous acid gas, sulphuretted 

 hydrogen, and muriatic acid gas ^ and, as a 

 general conclusion, M. Macaire was of opi- 

 nion, from these trials, " that many of the gases 

 are hurtful to vegetation ; but that they act on 

 them only during the absence of light." (Quart. 

 Journ. of^zr. vol. v. p. 301.) 



GAS-WORKS, the Refuse Matters of, as Fer- 

 tilizcrt. It is only within these few years that 

 the attention of the farmer has been attracted 

 to the various matters produced by the gas- 

 works now so common in all pans of England. 

 This attention, however, is confined at present 

 to only particular localities : while in one dis- 

 trict it is zealously used, and bought up with 

 avidity, in others it appears to be totally ne- 

 glected. In the vale of Kennet the farmers 

 clear away from the gas-works all the refuse 

 matters they can obtain, even at advanced 

 prices. Those of the valley of the Itchin, in 

 Hampshire, find it, in small proportions, an 

 excellent dressing for grass. 



The refuse matters which are produced 

 during the distillation of pit-coal in the gas- 

 works, consist of three substances ; the arnmo- 

 niacal liquor, the hydro-sulphuret of lime, 

 formed by passing the gas through lime to de- 



prive it of its sulphuretted hydrogen, and the 

 coal-tar; these substances are worthy of the 

 cultivator's attention, for they are all fertili- 

 zers of considerable value. Let us examine 

 them in the order in which I have enumerated 

 them. 



1. The ammoniacal liquor obtained from gas- 

 works is an impure solution of the carbonate 

 and acetate of ammonia ; and these salts, there 

 is little doubt, not only act as stimulants to 

 plants, but both the acids and the ammonia, 

 when decomposed, furnish direct food to, or 

 constitute parts of, vegetables. Carbonate of 

 ammonia has been detected in the stinking 

 goose-foot (Chenopodiuin olidum), by MM. Che- 

 valier and Lassaigne, and it probably exists in 

 other plants which are distinguished for their 

 powerful disagreeable odour. If the plants do 

 not contain ammonia, or its salts, it is the am- 

 monia either in the soil or the air which 

 affords them the nitrogen which enters into 

 their composition. (Annals of Phil. vol. xii. p. 

 231.) Hydrochlorate of ammonia has been 

 found in wood by M. Chevreul. (Jinn, de Chim* 

 68, p. 284.) 



There are many testimonials in favour of the 

 use, as fertilizers, of the salts of ammonia, 

 either in their pure state, or as found in an im- 

 pure combination with soot, or in the liquor of 

 gas-works. "Soot," said Davy, "owes part of 

 its efficacy to the ammoniacal salt it contains. 

 The liquor produced by the distillation of coal 

 contains carbonate and acetate of ammonia, 

 and is said to be a very good manure. la 

 1808, 1 observed that the growth of wheat in a 

 field at Roehampton was greatly assisted by a 

 very weak solution of acetate of ammonia." 

 (Lectures, p. 342.) The experiments of Mr. 

 Robertson with soot clearly show the fertilizing 

 effects of the soluble portion of it, which is 

 principally the salts of ammonia. He mixed 

 together, in order to form a liquid manure, six 

 quarts of soot in a hogshead of water. "Aspa- 

 ragus, peas, and a variety of other vegetables," 

 says this intelligent horticulturist, "I have 

 manured with this mixture with as much effect 

 as if I had used solid dung ; but to plants in 

 pots, particularly pines, I have found it ad- 

 mirably adapted; when watered with it they 

 assume a dark, healthy green, and grow strong 

 and luxuriant," (Card. Mag. vol. ii. p. 18.) 

 Care must be taken in using this, and all other 

 liquid fertilizers, not to make the solution too 

 strong ; it is an error into which all cultivators 

 are apt to fall in their early experiments. 

 Davy was not an exception; from making his 

 liquids too concentrated, he obtained results 

 which widely differed from his later experi- 

 ments. (Lectures, p. 170.) There is no doubt 

 but that the salts of ammonia, and all the com- 

 pound manures which contain them, have a 

 considerable forcing or stimulating effect upon 

 vegetation. In the experiments of Dr. Belcher, 

 upon the common garden cress, by watering 

 them with a solution of phosphate of ammonia, 

 the plants were 15 days forwarder than other 

 plants growing under similar circumstances, 

 but watered with plain water; and he also de- 

 scribes the experiment of a Mr. Gregory, who, 

 by watering one-half of a grass field with urine 

 (which abounds with the salt of ammonia), 



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