and Magazine of the Ceylon Agricultural Society. 307 



The oil is then squeezed out into a bank below 

 from which it is sucked up to pass through a 

 mechanical cleaner or— if there is no hurry — to 

 large tanks where impurities sink to the bottom 

 leaving the clear white oil to be drawn off from 

 the top. 



The place is full of all scrts of machinery and 

 another huge boiler has just been erected to 

 enable the company to keep the Mill going 

 without the otherwise necessary stops for boiler 

 cleaning. Coir making machinery has recently 

 been erected, so that every part of the coconut 

 can be used except the milk. Now that the 

 company has its own steamer there is no diffi- 

 culty in getting a full supply of nuts. The com- 

 pany, too, is fortunate in its manager, Mr. 

 Darby, who is particularly well qualified in every 

 way to make the Mill a success.— Malay Mail, 

 Jan. 25 



SANDY SOILS AND THEIR 

 IMPROVEMENT. 



The improvement of sandy soils is a subject 

 of wide intorest, and any means that would tend 

 towards effecting such improvement will be wel- 

 comed as much in this island as elsowhere, since 

 there are large areas of land that are charac- 

 terised by soils composed chiefly of silica. A com- 

 mon objection to most soils is the disproportion- 

 ate preponderance of one ingredient over the rest, 

 whether sand, clay or humus. The means of im- 

 proving soils must, of necessity, differ, inasmuch 

 as the preponderating ingredient invests a soil 

 with properties that have to be specially reck- 

 oned with. Thus the treatment of a heavy clay 

 will materially differ from that of a loose sand and 

 of both from that of a soil made up almost en- 

 tirely of organic matter. The New Jersey Ex- 

 periment Station recently published an account 

 of experiments made to improve sandy soils, 

 and a consideration of the results should be pro- 

 fitable to all who have similar problems to face. 



A fact that has to be recognised at the 

 outset is that sandy soils are, from their 

 very nature, unable to furnish as much plant 

 food or moisture to growing crops as those of 

 a clayey nature : further, that the coarseness of 

 sandy soils prevents them from retaining either 

 food or water when given to them. All who 

 have had anything to do with sandy soils will 

 readily admit that manures are easily washed 

 downwards into the sub-soil by rains, while dry 

 weather soon robs them of moisture. Indeed, 

 for successful cultivation, such soil needs a 

 tolerably well-distributed rainfall, a fairly com- 

 pact sub-soil, and a water-table near enough to 

 the surface for cultivated plants to draw upon 

 the moisture below. In very coarse soils of 

 this nature, capillary power is so limited that 

 they are unable to replenish from below the 

 loss of moisture by evaporation. Again, the 

 openness of light sandy soils, by admitting air 

 freely, accelerates the chemical and bacterio- 

 logical changes going on within them, so that 

 plant food is made more quickly available : 

 sometimes, indeed., too quickly— so that organic 



matter in the soil becomes exhausted sooner 

 than is desirable. Well aerated soils, there- 

 fore, favour bacterial activity, but the loss of 

 water from them interferes with the action of 

 soil organisms. 



To improve sandy soils, therefore, it is ne- 

 cessary to reduce their too open texture : — 



(1) by methods of tillage, such as cultivating 

 and rolling ; 



(2) by application of fiue-grained materials 

 or substances readily pulverised, such as clay 

 or loam ; 



(3) by the addition of large quantities of 

 humus-forming material, such as green crops or 

 " long " manure. 



A sufficiency of humus prevents too ready 

 access of air and increases the moisture-holding 

 capacity of a soil. Although sandy soils are 

 naturally poor in plant food, this does not pre- 

 vent the possibility of their improvement. Phos- 

 phoric acid and potash can be supplied at a 

 comparatively small cost, and nitrogen pro- 

 vided by means of green manures or animal 

 manures. The last- mentioned are not indispen- 

 sable and often too expensive ; in some cases 

 they are the means of introducing weeds or 

 fungus diseases. Green manuring is particularly 

 effective on account of the relatively greater 

 need for nitrogen and humus in light soils, and 

 the facility with which green crops are converted 

 into available plant food. The selection of these 

 will depend greatly on local conditions, the 

 number to select from being fortunately large. 



A mistake that is common is to expect 

 green crops to flourish even though there 

 is an entire absence of phosphoric acid, 

 potash and lime in the soil. That is not rea- 

 sonable, and where these ingredients are de- 

 ficient, the deficiency must be made good. If 

 this is done, and there is a fair rainfall, the 

 prospects of utilising green manures in tho way 

 suggested, are good. With the supplying of 

 humus to a sandy soil, and the increase of its 

 water-holding capacity, a uniform bacterial 

 development and a more uniform supply of 

 available plant food will be assured ; indeed, the 

 growth of bacteria is directly encouraged in the 

 presence of organic matter and moisture. 



The nitrogen-fixing bacteria of leguminous 

 plants find very favourable conditions in sandy 

 soils, and that for the following reasons : — 



(a) The small proportion of available nitro- 

 gen in them. 



(6) The free circulation of air which favours 

 the formation of nodules. 



(c) The frequent renewal of air which enable3 

 the bacteria to supply themselves with the ele- 

 ments of the atmosphere. 



It has been found that in compact soils, 

 nodules on roots are limited and found near the 

 surface, whereas in sandy soils they are well 

 distributed and occur at greater depths. 



There is an impression abroad that a legumi- 

 nous crop which succeeds in one place is bound 

 to succeed in . another, which is not so, and a 

 crop new to a given locality may entirely fail to 

 develop nodules because the proper organisms 



