404 QUEENSLAND AGRICULTURAL JOURNAL. [1 May, 1900. 
The samples of the soil received for analysis are now left for about ten © | 
fourteen days in a shady, dry place, assisting the process of drying by breaking 
up the lumps. The soil is broken up with a wooden mallet, and the stone | 
gravel, and sand separated out by passing weighed portions through sieves wit 
25, 144, and 576 meshes per square inch. The lumps remaining on the siev® | 
are gently broken up, and the stones cleaned from adhering soil by washing; 
the three sieves separating the raw soil into stones, gravel, sand, and fine 
earth. The air-dried fine earth passing through the finest sieve serves for the 
chemical analysis, but is also again, by washing with a stream of water of certain | 
velocity (elutriation), mechanically divided into fine sand and clay. Othe 
important properties of the fine soil are also determined; the most important 1 
are :— 
Reaction.— With the help of chemical tests, it is found if the soil has 2? | 
alkaline, neutral, or acid character. Acidity is generally a bad sign, shows 
the soil to be so dense that the air cannot enter sufficiently to help in the 
process of decomposition of decaying vegetable matter. ‘ i 
Weight of Soil per acre, to a depth of 6 inches, gives the actual weight ° 
the fine earth in tons per acre for a depth of 6 inches. Soils rich in organle 
matters (humus)—as, for instance, the Redland Bay soils—are light ; whereas 
soils poor in humus—as, for instance, samples No. 9 and 10 from Gindie, a™ 
Nos, 35 and 87 from the College hill—are very heavy. 
Capacity for Water.—Weighed quantities of the soils are completely 
saturated with water, and by another weighing it is ascertained how much wate? 
the soil is thus capable of absorbing. Soils rich in humus and clayey soils — 
absorb larger amounts of water. Samples Nos. 3, 4, 11, and 12 have tae 
capacity for water; samples Nos. 9, 10, and 87, a very low one. The | 
application of this yalue to the actual weight of soil per acre gives the welg 
of water absorbed in tons per acre 6 inches deep. 
Capillary power is of great importance, indicating the mechanical col 
dition of the soil, and also, indirectly, its composition. Soil rich in humus ane | 
also fine sand will haye a higher capillarity than very clayey soil. The capillarity ® _ 
ascertained by filling glass tubes with the fine earth, both ends being open and thé 
lower end closed with a piece of fine linen, and dipping in water After a certal? 
time (in our case six, twelve, twenty-four, thirty-six, and sixty hours), the — 
height of the water in the tubes is measured. Amongst the analyses show): — 
we find that the volcanic red soil of Redland Bay possesses a very high porosity 
and capillary power, the water rising after the first six hours already over } 
inches; such soil will always be well drained, and even in the wettest weather 
will never become water-logged. Another sample of soil |from the Hermitag® — 
State Farm (Nos. 3 and 4) fie no porosity, and very low capillary power ; eve? 
after sixty hours the water having risen only }-inch. ‘This soil is exceptionally 
wet, and, although it analyses well, it will grow no crops on account of its poo 
physical condition. We also see that, amongst all the soils given, these two at® 
the only ones with an acid reaction. 
Absorptive Power for Salts of a soil is of great practical importance. It 
indicates the power the soil possesses of retaining certain ausraniien compounds: ' 
Soils have not only the power of absorbing various gases, but also withdraw 
certain substances from watery solutions. A great absorptive power is ale 
a favourable sign of fertility, and it has a great importance for thé 
practical agriculturist, as it prevents waste of valuable food stuffs, formed Dy 
decomposition of organic matter, added to the soil by the rain water or appli 
in the form of farmyard or artificial manures. 
The power of absorption of soils varies for different substances, but, for 
practical purposes, it is sufficient to ascertain how much nitrogen is absor 
out of dilute solutions containing ammonia (ammonium chloride) ; and in ow 
analyses we state how many cubic centimetres (c.c.) (163 ¢.c. equal 1+ cubie 
inch) of nitrogen are absorbed by a certain quantity of soil. Subsoil No. is 
has a very high absorptive power, equal to 300 ¢.c. ; whereas soils Nos. 85 
37 have hardly any absorptive power at all. 
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