Research Article
The Feeding Value of Mangels
- T. B. Wood
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- 27 March 2009, pp. 225-232
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The paper describes attempts to test the following points—the comparative feeding value of Yellow Globe and Long Red mangels as constituents of a liberal fattening diet, the comparative feeding value of Golden Tankard and Long Red mangels, also as constituents of a fattening diet, and the comparative feeding value of Yellow Globe and Long Red mangels for store cattle.
The results point to the following conclusions:
The rates of fattening of individual animals vary so greatly that little reliance can be placed on the results of single experiments with the small numbers of animals commonly employed in feeding tests.
The feeding values of Long Reds and Yellow Globes were compared on seven occasions, and the results discussed according to the ordinary methods used in the theory of probabilities.
Some Characteristics of the Western Prairie Soils of Canada
- Frank T. Shutt
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- 27 March 2009, pp. 335-357
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It will be desirable, by way of preface, to say a word or two regarding the physical geography of the district, the soils of which form the subject of this paper.
The Rate of Fermentation of Ciders and Perries
- B. T. P. Barker
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- 27 March 2009, pp. 1-21
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The results of the work may be briefly summarised as follows:
(a) The rate of fermentation of ciders and perries made from different varieties of vintage fruit varies considerably.
(b) There is probably a relation between the rate of fermentation and the variety of fruit from which the cider or perry is made. Certain varieties, for instance, as a rule yield juices which ferment slowly, while others give juices which generally ferment at a rapid rate.
(c) The main factor in determining the rate of fermentation appears to be the nitrogenous matter present in the juice, which is assimilable by the yeast. The quantity of such substances present is generally insufficient for satisfactory nutrition of the yeast, and consequently the rate of fermentation is normally slower than would be the case if sufficient nitrogenous food were present to meet the full requirements of the yeast. The relative rates of fermentation of ciders and perries fermented under similar conditions are probably an index of the relative amounts of assimilable nitrogenous matter present.
(d) The state of ripeness of the fruit at the time of milling affects the rate of fermentation of the juice. During the course of ripening the rate becomes slower until a certain point is reached, which probably represents the period of perfect maturity of the fruit. Afterwards the rate increases in proportion as ripeness proceeds to decay. The degree of exposure of the fruit to direct sunlight also affects the rate of fermentation, the more exposed the fruit the slower the rate. In each case the result appears to be due to the quantity of assimilable nitrogenous matter in the juice being influenced.
(e) Direct influence on the rate of fermentation of the juice by any of the chemical constituents other than the nitrogenous substances has not been observed. If any have an influence, it is masked by other factors of greater importance. An indirect influence on the rate by the mucilaginous elements is occasionally met with, due to the formation of a clot which mechanically impedes the action of the organisms of fermentation.
(f) The rate of fermentation in practical cider-making does not appear to be materially affected by the fermentative powers of the kinds of yeast present in the juice. Normally there are present varieties which are capable of maintaining the fermentation at practically the maximum rate allowed by the nitrogenous constitution of the juice. “Dominant” fermentation with selected yeasts of high or low fermentative powers had comparatively little effect upon the rate.
(g) The aeration of the juice has a marked effect upon the rate of fermentation, the admission of air to the juice producing a decided increase in the rate.
(h) The temperature at which the fermentations are conducted affects the rate in the customary manner.
It is clear, therefore, that apart from the use of purely practical methods, e.g. filtration,—which it is not intended to consider here— a certain measure of control over the rate of fermentation of ciders and perries can be exercised by the cider maker, and that therefore the production of sweet and dry types of these beverages need not be more or less haphazard, as is commonly the case. By careful selection of the varieties of fruit used and by suitable blending of various types, combined with attention to the condition of ripeness of the fruit at the time of making, it should be possible to obtain a juice possessing the desired rate of fermentation, although some allowance for seasonal influences is necessary. These have not been considered above, as the work has not been extended over a sufficiently long period to allow of definite conclusions being drawn. At the same time it is fairly established that in some seasons the average rate of fermentation is much faster than in others. It would appear from the results as to the effect of direct sunlight as though the amount of sunshine during the period of ripening of the fruit upon the trees played an important part in seasonal influence. During the course of fermentation of the liquors the rate may be controlled to some extent by aeration and temperature.
Although the subject has been considered almost entirely from the point of view of the rate of fermentation, it should be mentioned that not only the rate but also the degree to which fermentation proceeds is involved. Although perhaps not invariably the case, as a rule fermentation can proceed to a further point in rapidly than in slowly fermenting juices. Accordingly no distinction has been made between them. In some cases the latter feature would more correctly express the facts than the former.
In conclusion I take this opportunity of expressing my indebtedness to Mr James Watts for his kindness in placing his factory at my disposal for experiments with selected yeasts; to the many cider makers and others, who have rendered considerable assistance in the direction of obtaining different varieties of vintage fruit required for the work; and to the various members of the staff of the Institute, who have carried out the practical work in the cider house.
The Effect of Partial Sterilisation of Soil on the Production of Plant Food
- Edward John Russell, Henry Brougham Hutchinson
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- 27 March 2009, pp. 111-144
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When soil is partially sterilised, either by heat or by volatile antiseptics like carbou disulphide, toluene, etc., it becomes more productive and capable of yielding larger crops. The effect of heat was discovered incidentally about 25 years ago by the early soil bacteriologists; the action of carbon disulphide was first noticed somewhat later by a vine grower who had used it to kill phylloxera. Both cases have since been studied by several investigators, notably Koch and Hiltner and Störiner; a paper was also recently published by one of us in which it was shown that the property is a general one, holding for all the soils and volatile antiseptics examined and for all the plants, excepting those of the leguminous order. Thus when a soil had been heated to 95° C. it produced two, three, or sometimes four times as much crop as a portion of the soil which had not been heated, whilst treatment with volatile antiseptics led to an increase in crop varying between 20 and 50 per cent.
The Ammonia in Soils
- Edward John Russell
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- 27 March 2009, pp. 233-245
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It has long been recognised that the amount of ammonia in soils cannot be determined by distillation with a solution of caustic soda or potash since these strong alkalis slowly decompose the complex nitrogenous matter and evolve a coutinuous stream of ammonia. Boussingault showed more than fifty years ago how this difficulty could be obviated. By using magnesia in place of soda or potash the decomposition of such substances as urea, asparagin, and albumin was not great even on long boiling, but when the distillation was carried out under reduced pressure at 38°—40° there was no decomposition at all. Ammonium salts, on the other hand, were completely broken up in these circumstances. He used this low pressure method in his researches on the ammonia content of urine, but does not appear to have applied it to soils. Sufficiently accurate results could, he considered, be obtained by distillation at 100°, and this method was for many years generally adopted. It gave results varying according to the nature of the soil from 10 to 100 parts of nitrogen per million (·001 to ·01 per cent.), which may still be found quoted in some of the agricultural text books.
The Mineral Constituents of Foods
- Herbert Ingle
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- 27 March 2009, pp. 22-31
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The importance of a “well balanced” ration in feeding animals has long been recognised, and most intelligent stock-keepers pay some attention to the albuminoid ratio of the foods they use.
Hydrolysis of the Protein of Linseed
- F. W. Foreman
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- 27 March 2009, pp. 358-382
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Every farmer who feeds stock finds the necessity for supplementing his home-grown foods, which are usually of a bulky nature containing large proportions of carbohydrate and fibre, by purchasing concentrated foods rich in nitrogen and fat. Experience shows that it is by no means a matter of indifference which concentrated food is selected to mix with any particular bulky food, and the trend of modern physiological chemistry seems to point to a definite explanation of this fact. According to modern views, the protein eaten by an animal is split normally by the digestive ferments into amino-acids and other crystalline nitrogenous substances. It is in the form of such comparatively simple substances that the animal absorbs its nitrogen from the alimentary canal, and from them that it builds up its own characteristic proteins.
The Inheritance of Horns and Face Colour in Sheep
- T. B. Wood
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- 27 March 2009, pp. 145-154
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1. As far as the characters under observation are concerned it is immaterial which way the cross is made. Reciprocally bred first crosses are identical.
2. The inheritance of horns is closely connected with sex. Large horns are dominant in the male, recessive in the female.
3. The meaning of scurs is not yet settled. Two kinds of scurs were observed, small round firmly attached knobs and thin loose scurs. The fact, which unfortunately was not observed until the later stages of the experiment, that the appearance of scurs is sometimes delayed until the animal is two years old, has given rise to an additional complication.
4. A horned ram may be either pure horned or heterozygous as regards that character. His purity can readily be tested by mating with a number of horned ewes. If all his ram lambs are horued he is presumably pure, if any of them are hornless he is heterozygous.
5. A hornless ram must be pure hornless. His purity can be tested by mating with a number of pure hornless ewes, when all the progeny are found to be hornless.
6. A horned ewe must be pure horned. Her purity can be tested by mating her with a pure horned ram. All the ram lambs produced will be horned, for horns are dominant in the male. All the ewe lambs should be horned if she is pure. It may be several years before she bears enough ewe lambs to enable the experimenter to state with anything like certainty that she breeds true to horns. It is here that the chief difficulty of working with large animals on Mendelian lines is found. The females produce only one or two young in the year, so that several years must elapse before a female can be thoroughly tested.
7. A hornless ewe may be either pure hornless or heterozygous. She can be tested by mating with a hornless ram. The same difficulty again arises, in fact it must always arise in the case of testing slow breeding animals. The males are readily tested, but the testing of the females is so slow that it must often be uncertain. This is the explanation of the common and very true statement that the way to improve a flock is to use good males. Males are readily tested and their purity as regards desirable characters is therefore very soon assured. Several generations may have been bred from a female, and her blood diffused through the flock, before the breeder can be sure that she breeds true to the type he wants.
8. The occasional occurrence of scurs in Suffolks already referred to is probably explained by the dominance of the hornless condition in the female. A hornless ewe may be heterozygous. This can only be found out by a breeding test, and may easily be overlooked in practice. Her progeny would then mix with the flock, and a small proportion of their ram lambs would produce scurs.
9. There is no dominance of white face over black or vice versd. The first cross as regards face colour is intermediate between the two parental types. Pure white and black faces segregate in the second generation. The black face is not a simple character, since the number of speckled faces in Fa is far too large, and the speckled faces include several distinct types of pattern.
10. Woolly and bare heads appear to be a pair of characters which blend in the first cross but segregate again in later generations.
11. A number of striking instances of recombination have beenobserved. For instance, horns, woolly poll and face, and black face are combined in the ewe, Plate XII, Fig. 15. She has been shown to breed true to horns, but her purity as regards woolliness and blackness of face has not as yet been tested. Another example is the ram shown in Plate XII, Fig. 18, which combines the bare head and hornless character of the Suffolks with the white face of the Dorsets.
12. Finally attention should once more be drawn to the difficulties of experimental breeding with large animals. The slowness and lack of certainty in testing the females, and the troubles arising therefrom, have already been dilated upon. Another difficulty is the complicated nature of what might have been hoped to be simple characters. Points of economic importance such as would be likely to appeal to the butcher, the dealer or the wool merchant, are hardly likely to turn out less complicated than horns or face colour. The experiments described above have suffered greatly from the fact that it was impossible with the comparatively small area available to keep more than a very small proportion of the rams until they were old enough to show all their characters. The unsatisfactory state of the evidence given above as to the question of scurs is in part due to this. It is however a difficulty which would disappear with increased resources.
The Action of Heat and Antiseptics on Soils
- Spencer Umfreville Pickering
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- 27 March 2009, pp. 32-54
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When soils are treated with antiseptics, such as carbon disulphide, chloroform, benzene, ether or paraffin oil, they undergo chemical change, and the soluble organic matter in them is increased, just as in case of their being heated; they also exhibit the same inhibitory effect on the germination of seeds that heated soils do.
The different antiseptics differ in the intensity of their action, but the inhibitory substance formed is probably the same in all cases, and also the same as that formed by heat, for the quantity formed has the same effect on seeds, whether produced by antiseptics or by heat.
On keeping treated soils for a few weeks at a summer temperature, some of the organic matter which was rendered soluble becomes insoluble, and the inhibitory action is reduced. This is also the case with heated soils, especially when repeatedly watered; though with unheated soils under similar conditions the soluble organic matter increases.
The treatment of soils with antiseptics induces a change equivalent to that obtained by heating the soil to 60°—75°, and this may be sufficient to account for the increased growth observed in plants grown in them.
The production by heat of a substance inhibitory to germination appears to be a property common to all soils, twelve instances having been examined: the proportion of it formed depends on the increase in the amount of organic matter rendered soluble by heating; but the actual amount of the soluble organic matter in the heated soil is not always a criterion as to the intensity of its inhibitory action, and still less is the amount of soluble organic matter originally present in the unheated soil, though in the majority of cases it may be so. There appears to be no connexion between the fertility of a soil and the extent to which it is altered by heating.
Soils in their natural state appear generally to contain a certain amount of this inhibitory substance, as they act less favourably towards germination than pure water does: whether in any cases soils can act more favourably than water—as the earlier experiments had indicated they could—is open to doubt, but the probability is in favour of their doing so. So far as the instances now examined are concerned, the richer soils, and those containing most soluble organic matter, are slightly less favourable to germination than the poorer soils.
Estimation of Calcium Carbonate in Soils
- F. S. Marr
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- 27 March 2009, pp. 155-160
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Boiling acid at atmospheric pressure decomposes organic matter in soil with evolution of carbon dioxide, and thus renders the results obtained for carbonate too high. Where there is a fairly large percentage of carbonate, the error introduced in this way is of no great importance, but in soils containing less than 1% of calcium carbonate and especially in acid soils, the error introduced by thus boiling with acid may be very considerable.
The weaker the acid used the better so long as there is fair excess. The writer recommends for acid soils and those containing low percentages of carbonate (as can be seen by making a rough preliminary test), 2 c.c. of strong hydrochloric acid and about 100 c.c. of water: 20 grams of soil should be used when the amount of carbonate is small. The acid may be conveniently added by making up a solution containing 100 c.c. of strong hydrochloric acid per litre, and introducing 20 c.c. of this solution along with 80 c.c. of water. For most soils, 5 c.c. of strong hydrochloric acid to 100 c.c. of water will be found convenient.
If possible distillation under reduced pressure should be used, as under this condition practically no decomposition of organic matter takes place, while carbonate is readily decomposed: the distillation should be continued for twenty minutes at a temperature of about 50° C.
The Effect of Earthworms on Soil Productiveness
- Edward John Russell
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- 27 March 2009, pp. 246-257
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Gilbert White devotes one of his letters to earthworms. “Worms,” he says “ seem to be the great promoters of vegetation, which would “ proceed but lamely without them, by boring, perforating, and loosen-“ing the soil, and rendering it pervious to rains and the fibres of plants, “by drawing straws and stalks of leaves and twigs into it; and, most of “ all, by throwing up such infinite numbers of lumps of earth called “ worm-casts, which, being their excrement, is a fine manure for grain “and grass… the earth without worms would soon become cold, hard-“ bound, and void of fermentation, and consequently sterile.” Sixty years later, in 1837, Darwin published a paper, in which he showed the important part played by worms in the formation of vegetable mould. Further observations were recorded by Hensen in 1877. Agricultural chemists did not, however, generally make use of any of this work, and it was not till 1881 that the publication of Darwin's Earthworms and Vegetable Mould directed so much attention to the subject that the action of earthworms could no longer be disregarded. Several investigations have since been made into the part played by earthworms in promoting fertility, perhaps the best known being those recorded in Wollny's Zersetzung der organischen Stoffe.
“Fatness” as a Cause of Sterility
- F. H. A. Marshall, W. R. Peel
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- 27 March 2009, pp. 383-389
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The general experience of breeders, supported by statistical evidence in the case of sheep, has shown that a good thriving, but not over-fat, condition during the breeding season is that which is most conducive to a high fertility. It has been shown further that the practice of “flushing” or “springing” ewes (i.e. artificially stimulating them by means of an extra supply of special food) shortly before and during tupping time results in an increased number of births at the succeeding lambing time. On the other hand, an excessive quantity of nutriment producing a great deposit of fat is known to be prejudicial to the proper discharge of the reproductive functions. No better example could be given of the way in which overfeeding results in a condition of sterility than that of the barren shire mares which have been a noteworthy feature at many agricultural shows. It is a matter for regret that those animals, whose appearance justified them as prize-winners, should in many cases have proved valueless as brood mares owing to the methods of feeding to which they had been subjected in preparing them for show. The association of sterility with a too fattening diet is as common among cows, sheep and pigs as it is among mares. Thus Cornevin writes: “Chaque aunée, dans les concours, nous avons sous les yeux des spécimens des plus belles races ovines et porcines qui, véritable modèles de bonne confirmation, de puissance assimilatrice et d'aptitude á prendre la graisse, restent stérile.” Moreover, Mr Edward Brown, the honorary secretary of the National Poultry Organisation Society, ascribes the decrease in egg production by poultry during the winter months in part at least to overfeeding.
Studies of the Changes occurring in Heated Soils
- Spencer Umfreville Pickering
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- 27 March 2009, pp. 258-276
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The water extracts obtainable from soils are of constant composition as regards organic matter when the time allowed for the extraction varies from 20 to 320 minutes, the temperature from 7° to 23°, and the proportions from 5 to 10 of soil to 100 of water. The inorganic matter is not affected by the time, but is by the temperature and proportions.
The increase in soluble matter produced by heating a soil, and the accompanying toxic qualities towards the germination of seeds in it, is gradually reduced by exposing these soils in a moist condition to the air, even under aseptic conditions, but is not reduced, when the soils are kept moist in the absence of air. The destruction of the toxic substance is probably, therefore, due to oxidation.
Unheated soils, or soils heated only to a low temperature, exhibit on keeping an increase in soluble matter; this occurs whether air is admitted or not, and this change, therefore, is probably not an oxidation process: the substance formed, moreover, in such cases appears to have little or no toxic action on germination. This increase of soluble matter, due to the formation of a non-toxic substance, is preceded by a preliminary diminution of soluble matter, precisely similar to the diminution of toxic matter occurring continuously in the more highly heated soils: such toxic matter, therefore, appears to be present in all soils, whether heated or not, though, in the latter case, it is present in such small quantities that it soon becomes completely oxidised.
Air-dried soils, heated and unheated, when kept for some months show an appreciable reduction in soluble constituents, and also in toxic properties (where such properties were originally present), closely similar to the reduction exhibited by moist soils kept in air for about ten days.
The Amount of Free Lime and the Composition of the Soluble Phosphates in Basic Slag
- C. G. T. Morison
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- 27 March 2009, pp. 161-170
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Basic Slag owes its value as a source of phosphoric acid to the fact that it is essentially basic in its character, and can be used on land where an acid manure of the character of superphosphate is not to be recommended.
As no figures were available on the subject it seemed interesting to determine how much of the lime which it contains existed in the free uncombined condition. It has been stated that in some cases this is as much as 20%.
With a view to this determination four samples of freshly ground slag were obtained direct from the makers through the kindness of the Lawes Chemical Manure Company.
A Bacterial Disease of Swedes
- J. H. Priestley, A. E. Lechmere
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- 27 March 2009, pp. 390-397
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A disease of swedes is described and attributed to the action of an organism, probably Bacillus oleraceae (Harrison), but closely allied to Pseudomonas destructans (Potter). It is suggested after consideration of its appearance on various culture media, that these two organisms may be different growth forms of the same parasitic species.
The Yeast Flora of Bottled Ciders
- Elsie B. Pearce, B. T. P. Barker
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- 27 March 2009, pp. 55-79
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The work described in this paper deals exclusively with the yeast flora of certain bottled ciders. It was undertaken as a section of an extensive scheme of investigation of the organisms which are concerned in the fermentation of English-made ciders. Apart from the more purely biological side of the question the main objects of the whole scheme are to determine how far the customary method of conducting the fermentation of cider in this country is satisfactory, and whether it could be improved, from a practical point of view, by certain modifications or by the substitution of other processes, such, for example, as the use of selected yeasts.
Note on the Composition of Soot
- H. W. Harvey
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- 27 March 2009, pp. 398-399
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The value of soot as a manure depeuds upon the ammonium salts which it contains, as well as upon its beneficial effect on the texture and colour of the soil, and its power of diminishing the ravages of slugs and small snails upon a young crop. In various samples which from time to time have been submitted to analysis the percentage of nitrogen present has been found to vary within very wide limits, from 0·5 to 7 per cent., and it is usually stated to be present in the form of ammonium sulphate; actually it occurs for the most part as ammonium chloride.
The Genetic Classification of Soils
- N. M. Tulaïkoff
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- 27 March 2009, pp. 80-85
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All classifications of soils yet proposed may be divided into two groups: (a) scientific classifications which are based on the natural characteristic of the soil, and (b) “applied” classifications which are based on the suitability of soils for certain crops, or on the revenue that may be derived from them.
Bordeaux Spraying
- Spencer Umfreville Pickering
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- 27 March 2009, pp. 171-178
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Bordeaux mixture has practically superseded every other fungicide for general use, and two or three sprayings with it have become part of the annual routine of the fruit grower in most countries except our own, whilst in viticulture, its use is quite indispensable, and potato growers are applying it more and more every year. Any means for simplifying or cheapening the application of it, are, therefore, of great importance.
Plant-growth in Heated Soils
- Spencer Umfreville Pickering
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- 27 March 2009, pp. 277-284
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The existence of a toxic substance in heated soils, and the coexistence of two changes of an opposite character when such soils are kept—the one resulting in the oxidation and destruction of the toxin, the other in an increase of the soluble organic matter present—seem to offer an explanation of certain anomalies which have been observed in the growth of plants in these soils, to which allusion has already been made; provided, always, that this toxic substance is toxic towards plant-growth in the same way as it has been found to be toxic towards seed-germination.