The Working Farmer 3(7): 157-158 (Sept 1, 1851)
Irish Peat Charcoal as a Manure

The English papers are still teeming with the praises of this article as a deodorizer, and many claim for it special properties not common to all carbonaceous matter. We have fully tested and published all the facts relative to charcoal made from peat, wood, &c, &c. We have also proved satisfactorily that the peat or turf decomposed by the salt and lime mixture, has all the qualities of charcoal in absorbing odors, retaining ammonia, &c, &c.

The simple facts are, that either charcoal dust or decomposed peat or muck, if mixed with nightsoil or urine, or any other substance having offensive, odors, will absorb these odors and render the mass inodorous; or, if charcoal dust or decomposed peat or muck be mixed with soils, such soils will be rendered more retentive of manures and hence more economically workable. Any of these deodorizers by long exposure to the atmosphere, seem to lose their power of absorbing odors, but upon close investigation it will be found that they have already taken a full dose of gases from the atmosphere, and therefore can receive no more until their current contents is used up by growing plants, and it is for this reason that old charcoal hearths are found to act so powerfully as manure. When charcoal dust or decomposed peat (freshly made) is added to soils in their pure state, no material effect will be produced until by time they shall have received and retained ammonia from the atmosphere, when the good effects of the retention of the ammonia will become evident. Nor does the benefit cease with the first action, for it will repeat itself each year, the carbon taking up new quantities of ammonia as fast as the old one is absorbed by plants. The following article is from the Farmers' and Gardeners' Journal.—[ED.

We are always anxious to present both sides of a question. And there are few questions, either in natural history or morals, which have not at least two sides—as if to show how extreme opinions were to be avoided, to tend to moderation in general opinions, and to induce that care and caution in all investigations of a scientific character which modifications in circumstances will always render necessary.

We some weeks ago alluded to the subject of the Irish peat charcoal as a manure, or at least as a vehicle of absorbing or deodorizing manure, and in reviewing the opinions and experiments of Professor Anderson, the chemist to the Highland Society of Scotland, and the practical experiments of the Yorkshire Agricultural Society, we were forced to the conclusion that, valuable as the Irish peat charcoal was as a deodorant, useful as it was as a convenient vehicle for conveying the cloace of our towns away to the soil, to be used as a manure—it did not seem to possess in itself much manurial qualities; and Dr. Anderson went so far as to express very grave doubts that it possessed any considerable powers of absorbing the elements of manure. Still, the demand has so increased for the charcoal, that the Irish Amelioration Society has been utterly unable to supply the demand, and a society has been organized, we believe, in London, for the purpose of charring the English peat, and applying it to the same purposes as the peat bog of Ireland is used for.

Side by side almost with Dr. Anderson's report comes that of Dr. Sullivan, chemist to the Museum of Irish Industry, and an outline—a very brief one necessarily—of his paper we propose to give to our readers.

Commencing with the power of certain substances to condense and retain certain foreign matters in their pores and structures, he gives a very interesting account of the modus operandi of absorption generally; he goes on to show the power possessed by the Irish peat charcoal to absorb ammonia—a fact, it will be remarked, to which Dr. Anderson applied his experiments, and with what result we shall see.

He first heated the charcoal to redness—a precaution which we fear Dr. Anderson did not see the necessity for adopting; for it must be evident that whether the absorptive powers of the charcoal are taken into consideration for the purposes of manure, or whether it is to be used simply as a deodorant, its powers must be tested fresh, and not when partly saturated. And this for the best of all reasons; for if used as a manure, all the ammonia it may have absorbed by exposure or otherwise is useful for manure; and if it be deodorization which is the object, it is necessary to have it fresh to completely effect the object of the experimenter. Hence Dr. Sullivan clears his ground all the better for first ascertaining that it is free from ammonia before he makes his experiment.

This heated charcoal from which the nitrogen was so expelled, having been placed under a bellglass, in which was a small capsule of water, but with free ingress to the air, absorbed of gases and water 6.815 per cent. in 24 hours, and 16.606 per cent. in fifteen days.

On ammonia being added to the capsule of water, in another specimen, it yielded after two days' exposure 0.304 per cent, of ammonia, seven days 0.411 per cent, in fifteen 0.561 per cent.

But Dr. Anderson experimented on the mixture of peat charcoal and cloace, and so does Dr. Sullivan give his results on the subject. The latter took a portion of night-soil, and neutralized it with a given weight of sulphuric acid, and evaporated the mass to dryness; on analysis it contained only 1.437 per cent, of nitrogen. Now Dr. Anderson takes for this data specimens of peat charcoal containing 0.91 per cent, of nitrogen, or only some one-half per cent—one pound in two hundred—more ammonia in the peat charcoal which he selects as a specimen to test the absorptive power of the preparation, than there is in the night-soil itself as found by Dr. Sullivan. Surely this explains the reason why the Scottish doctor found only 0.88 per cent, of nitrogen in a mixture of charcoal and urine, and some 0.87 in the charcoal itself!

The doctor, moreover, analyzes several specimens of the peat charcoal treated with various substances, and he found that when two parts of charcoal and one part of night-soil were added together the product was—

  Per cent.
Water 28.470
Organic matter 62.746
Ash 7.514
Nitrogen 1.270
Or equivalent to ammonia 1.541

Now there is a difference here between Dr. Anderson and Dr. Sullivan which we are utterly unable to account for—the one makes the nitrogen of the above mixture 0.840 per cent., while the other makes it 1.270 per cent!! Now Dr. Anderson made one specimen, saturated with night-soil as he describes it, come very near to this analysis, or 1.25 of nitrogen; and in their trials of the peat charcoal saturated with urine they are more nearly the same—the one being 1.20, the other 0.964.

The ash of the night-soil-treated peat charcoal is thus given by Dr. Sullivan:

  Per cent.
Potash 0.471
Soda 4.987
Lime 21.161
Magnesia 10.554
Alumina 0.077
Peroxide of Iron 9.874
Phosphoric acid 6.109
Sulphuric acid 19.754
Hydrochloric acid 5.734
Sand and silica 7.540
Carbonic acid 6.139

Now there is a fairness in Dr. Sullivan which shows that he is not by any means the advocate; but he differs from Dr. Anderson in the most material elements of calculating the value of the product; for while the latter concludes "that the absorptive power of peat charcoal for ammonia is so small as to be practically of no importance, and its use for this purpose cannot be recommended to the farmer—Dr. Sullivan, more reasonably as we believe, concludes "that peat charcoal, although its absorbent powers for ammonia in solutions are small, yet, owing to the greater part of the ammonia at first absorbed being gradually transformed into stable compounds will be found effective enough as an absorbent of that substance in cases where the evolution of ammonia from the decomposing nitrogenous substances is slow and in small quantities, which is the case in general with night-soil and most other matters employed in manure;" and "that peat charcoal mixed with night-soil and other faecal matters forms a valuable mixture"—and we are the more willing to give the utmost credit to his statements, from the fact that he declares that its price is at present too high, and that peat is itself a better absorbent than its charcoal.