APRIL, 1909.] 



SCIENTIFIC AGRICULTURE, 



THE ACTION OF HEAT AND 

 ANTISEPTIC ON SOILS, 



Summary. 



When soils are treated with antisep- 

 tics, such as carbon bisulphide, chloro- 

 form, benzene, ether or paraffin oil, 

 they undergo chemical change, and the 

 soluble organic matter in them is in- 

 creased, 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 in- 

 hibitory 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 render- 

 ed soluble becomes insoluble and the 

 inhibitory action is reduced- This is 

 also the same 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 anti- 

 septic 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 examin- 

 ed ; 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 or- 

 ganic 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 ferti- 

 lity 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 

 bad 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 slight- 

 ly less favourable to germination than 

 the poorer soils.— Woburn Experimental 

 Fruit Farm, 19th Report, 1^08. 



THE VALUE OF RECORDS. 



Few enterprises make much progress 

 until the things with which they de^l 

 are measured and recorded, so that 

 accurate comparisons can be made. 

 This is eminently true alike of the 

 chemical and physical sciences and of 

 many forms of industrial work, includ- 

 ing agricultural operations. 



When towards the close of the 

 eighteenth century James Watt induced 

 the owners of the Cornish mines to sub- 

 stitute his engines for the form then in 

 use, he took as payment for these engines 

 one-third of the saving effected in the 

 coal consumed. This arrangement led 

 to accurate measurements, not so much 

 with the idea of savins: fuel, but in order 

 to ascertain the amounts to be paid. 

 When, in 1800, this weighing of the coal 

 ceased, the character of the work fell off 

 and the coal consumption increased. 

 Soon afterwards an accurate system of 

 recording and reporting was again intro- 

 duced, with such excellent results, that 

 it is said that the practice of keeping 

 accurate records is thought to have been 

 attended with more benefit to the dis- 

 trict than any other single event, ex- 

 cepting only the invention of the steam- 

 engine itself. 



In connexion with planting industries 

 in the West Indies, measurements, 

 weighings, and records are in many 

 cases very imperfect, so that progress is 

 retarded thereby, and it is more than 

 probable that the above experience 

 might be repeated by agriculturists in 

 these islands. The analogy is fairly 

 close between weighing coal and weigh- 

 ing canes. In the case of the Cornish 

 miners the weighing was undertaken for 

 a specific purpose, but was ultimately 

 found to have important collateral 

 results. Doubtless the question fre- 

 quently arose : 4 What is the good of 

 weighing the coal? It does not make 



