Annals of Horticulture, 5: 430-432 (1950)
Jasper W. Rogers, Esq., C. E.

CHARCOAL has been long known to possess considerable merit as a fertilizer, although it has not attracted much public attention till within the last few years. We do not here open the inquiry as to how charcoal acts beneficially on the soil, but assume the fact as now abundantly attested by experience. It would appear, that, whatever the value of wood charcoal may be in this respect, (and past experience speaks for the most part of this form of charcoal,) that of charcoal made from peat moss is much greater.

At a meeting of the Botanical Society of London, on the 8th of July, the subject was introduced by Jasper W. Rogers, Esq., C. E., who exhibited various samples of the charcoal in different states, and well adapted for cultural purposes. Mr. Rogers says :—

"Peat charcoal possesses several advantages over wood charcoal. The small quantity of pyroligneous acid originally contained in the peat is entirely dispersed in the preparation; hence, no acetic odour arises, which is complained against in wood charcoal, and produces severe headache. Again, its light and pure blaze gives a greater extent of calorific effect, because it extends itself generally over the surface to be heated, and carries with it no smoke. Peat charcoal emits a blaze, which wood charcoal does not. But one of its great advantages is the power of fertilization in its individual state.

"In the year 1845, I first brought the fact under the consideration of the Relief Commissioners of Ireland, in a report I was called upon to make upon the subject of peat fuel. The theory was then smiled at, both by scientific men and scientific bodies; but it has happily outlived opposition. The Royal Agricultural Society offered a prize the following year for the best essay on the subject; and now, a great number of farmers save every bramble from their hedges to make charcoal, and by drilling it in with their seeds, produce great advantage to the crops.

"But I would draw special attention to that which I deem to be the main and grand advantage which peat charcoal possesses in so singular a degree, namely, that of perfectly deodorizing and disinfecting animal excretiae. I say, peat charcoal, because the same capability does not exist in wood charcoal generally, and in several descriptions, not at all; for instance, the charcoal of lignum vitae, teak, and hard oak, has, in fact, no deodorizing power. This capability increases as the wood becomes softer and more porous, and that which I have found to have most effect, is the charcoal of the willow. In addition to peat charcoal, specially prepared for deodorizing, being infinitely more porous than that of wood, it perhaps contains some other property not yet discovered, for I have no hesitation in saying we are all, as yet, strangers to its eminently useful powers, and that it is a subject particularly worthy of investigation."

"For fertilizing purposes, the charcoal prepared from the peat in an uncompressed state appears to be best adapted, although a more dense material can be obtained. Indeed, by a particular process, "the density of peat charcoal can be made to exceed that of wood charcoal. It is only to make the peat as dense as wood, to produce equal density in charcoal; and this is very simply done by exhausting the chamber in which the piece of peat is compressed, at the same instant that the compression commences. The atmospheric air being withdrawn from beneath, the aqueous matter must follow, and rush into the air-pump; the resistance, therefore, presented to the power of pressure, is simply the fibre of the peat; while the vacuum produced underneath gives the aid of the natural pressure of the atmosphere, at top, to assist the operation. Thus, the imaginary difficulty of producing dense charcoal from peat has been overcome—so simply, that it is only to be wondered at that it had not been done long since. The present market value of peat charcoal varies from 4l. to even 8l. or 9l. per ton, the latter being the average price of wood charcoal sold in London for culinary purposes; it may be sold with large profit for much less."

"In its natural state, peat moss has several peculiarities. It delights in moisture, and yields it up most unwillingly. It contains, in different small proportions, ammonia, pyroligneous acid, tar, &c, and also a very singular production, a ' fatty matter,' which, when purified, closely resembles spermaceti, and makes a very beautiful candle. Mr. Reece Reece has recently patented a process for the extraction of these articles, carrying out the production of iron from ore which is upon the property. Possibly 'Price's patent wax candle' may yet be rivalled by 'Reece's bog spermaceti.' To speak seriously, the production is really beautiful, and gives a pure and strong light. The question to be solved, however, is, Can it be obtained in sufficient quantity to be profitable? It is found in its natural state, at times, in small quantities collected together by some peculiar local filtration, or, perhaps, affinity, which draws it from the mass around to one spot. The matter, when pure, is about the colour of butter. The superstitious tradition of the peasantry is, that the Fairies hide it for their use, and hence it is called 'Fairy butter.' It is but rarely found in that state, and is then treated with great reverence. Another property of the peat moss is the singularly preservative nature of its water, which is of a dark brown colour, almost approaching to black. It has been said to contain a tannin quality, but analysis proves to the contrary. However, its power of preserving animal matter from decomposition is very extraordinary. Human bodies have been found in bogs, undecomposed, which must have been long buried."

Mr. Rogers, it will be seen, assumes that peat charcoal is not only valuable in itself as a fertilizer, but may be made even more so as a fertilizing agent, at the same time that it is employed to deodorize and disinfect putrescent animal faeces. On this point he observes :—

"The fact that the health of towns mainly or entirely depends upon the almost immediate removal of their refuse, is at present so well understood, that it cannot be requisite to enlarge upon it. All are now aware that in the ratio of the retention or removal of such matter, is the average of life or death; and the question on that score comes upon us now in so fearful a form, that it cannot need any adjunct to enlist our energies in the cause of our own preservation. It is singular, that that substance which produces the evil, and which has hitherto spread disease amongst us, should contain not alone the principles of health, but also of wealth; and perhaps it may be said that nature has provided in proportion to the mass of beings congregated together, the means for their subsistence, in the very refuse or matter which we permit, by our neglect, to produce so much evil.

"It has long been known to science, that the excretiae of mankind contains a greater amount of the properties essential to the fertilization of plants, than any other substance. To its most careful preservation and use China owes the capability of supporting a population almost incredible, with reference to the extent of the soil under cultivation; and in the ratio of the introduction of excretiae as a manure, on the continent of Europe, has been the increase of agricultural profit. There its use is now almost universal, while we, of England, neglect that which, perhaps, as in most other things, we should have led the way in using. But there have been many difficulties to contend with in its introduction as a marketable fertilizer.

"Firstly,— Its collection without annoyance and evil.

"Secondly,— Its deodorization, so as to admit of convenient transport.

"Thirdly,— Its preservation, in a manner to retain its valuable qualities as a manure.

"To obviate these evils several chemical deodorizers have been produced, but being liquids, the advantages proposed to be obtained became neutralized by the increased difficulty of reducing the matter to a sufficiently dry state for transport. Happily, however, nature has provided, by a production of the vegetable world, a simple remedy for this difficulty, in peat charcoal. It is perhaps the greatest absorbent known; it will take up and retain above 80 to 90 per cent, of water, and at least 90 or 100 volumes of those noxious gases arising from animal excrement and other putrescent matter. Hence its great value for effecting deodorization, and for retaining all the value of the liquid as well as its volatile products.

"Equal parts of prepared peat charcoal and excretiae will, under almost every circumstance, accomplish this if properly intermixed—producing a manure of almost incalculable value. The proportion of charcoal may be less in some instances, even down to one-third—if very intimate mixture be made, and the charcoal be properly prepared.

"This mixture is quite dry, and can be transported in bags, or even in bulk, by almost any public conveyance. Its value as a manure cannot, I believe, be over-estimated. In all the trials made with it, both by myself and others, the effect is singularly great; but it cannot be otherwise, when we consider what the compound contains. Professor Phillips's analysis of peat charcoal (the same as on the table) for deodorizing purposes, is as follows:—

Carbon 79.24   
Hydrogen 2.20  
Nitrogen 0.54  
Oxygen 6.44  
    Combustible matter 88.42
Sand and Clay 2.48  
Oxide of Iron 1.66  
Phosphoric Acid 0.34  
Silicate of Potash 0.93  
Chloride of Sodium 2.53  
Carbonate of Lime 1.85  
Sulphate of Lime 1.44  
Loss: 0.30  
    Incombustible matter 11.58

"Now, add to this, ammonia, gluten, phosphates, urea, &c. contained in human excretiae, and it will be obvious that it is perhaps impossible to produce a combination more perfectly adapted for the food of plants. All the elements for their nurture are interwoven, it may be said, into every grain of charcoal; carbon, the staff of vegetation, is the base, and the whole are yielded to the plant together. It is well known that the strongest affinity exists between the ammoniacal and other atmospheric gases, and carbon; and here again a singular advantage arises. Every shower of rain that falls, gives a greater supply of the ammonia, salts, &c. contained in that rain, to the charcoal. Hence it is not only the means itself of giving health and strength to the plant, but every little grain becomes a reservoir, not alone of manure, but moisture, both of which never cease to act upon and invigorate the vegetable."

Mr. Rogers then enters into some very singular calculations as to the value of the refuse which is at present permitted to enter the sewers of the metropolis, and to pollute not only the river into which they empty, but the atmosphere, into which they evolve gases of the most deleterious nature. We shall quote some of his statements upon this matter:—

"If these be facts, why should we permit one ounce of that which now produces disease and death amongst us, to be lost? Why should we, for health sake—and why should we, for the sake of our pockets? For I shall undertake to show by a few figures that every one who has a family of six, may, if proper means be made use of, not only increase their health, but add to his wealth to the extent set forth.

"The average of excretiae yielded by a human being per annum is 10 cwt. Six will therefore yield three tons: add to this, say three tons of charcoal, and you will have of manure six tons. Now although this manure must be infinitely superior to guano, which sells at 10l. to 12l. per ton, suppose we estimate it at 5l.; the gross value of the manure will therefore be 30l. per annum!

"From this we have to deduct the cost of the charcoal, which can be produced in London at from 2l. to 3l. per ton, say at 2l. 10s. Therefore 7l. 10s. and the expense of collecting and intermixing will be the whole deduction from the 30l. In order to be entirely on the safe side, add 7l. 10s. for these expenses, and by this very fair estimate it will be seen that the smallest possible value of the household produce will be at least 15l. per annum.

"That you would perhaps laugh at this I anticipated, for I smiled at it myself when I first worked out the figures; but though laughable, this is, nevertheless, fact, and I am willing to submit the whole to any public test that may be suggested. But figures in the aggregate are more startling still.

"The average number of houses within the districts of London, assessed above 10l. per annum, may be assumed as 200,000; consequently, the total of assessed taxes of that class may be taken as 2,000,000l. Now, if the inhabitants only determined on ridding themselves of the evils that encircle us by the present fearful sewage system, and saved that which nature intended as a means to produce food in abundance, they would not only confer a great boon upon the population generally, but the profit to be had in money would amount, at 15l. per house, to 3,000,000l. per annum; or, in other words, that class of the citizens of London who pay those taxes, may save them, and perhaps put into their pockets 1,000,000l. yearly, at the same time that they preserve the health of the city, and prevent the disgraceful and death-dealing fact of their noble river being converted into a monster cesspool."

Mr. Rogers has, it appears, placed before the Sanitary Commission a proposition founded on the facts above named, and has pointed out how, in his judgment, the whole of London may be freed from its present dreadful sewage evils, most ample profits being returned, in place of millions being expended in trying to get rid of that which should be carefully saved.