March i, 1895. THE TROPICAL 
AGRICULTURIST. 
577 
of efficiency with the minimum of smoke and ash. 
The experiments are gradually approaching conclusion, 
and will be embodied in a report of the use of the 
Admiralty. 
Many of the native drugs con'n'n active principles 
which have n-ver be n sci ntifically investiga' e ', and 
others appear to contain alkaloid i which are isomeric 
with those known to science, and yield reactions which 
differ in i npor ant r spscts from those of the k lown 
substanc s. In especial the sp j cies of conine has 
colour reactions differing in important re-pe.tsf om 
either of the k own bodies, in p articular giving a red 
c 1 uration with n ither nitric nor sulphuric adds 
One of the dried roots made us i of by the native 
doctors contains a volatile liquid a k iloid, similar in 
physical properties to both conine and nicotine, but 
entirely distinct in its chenii -al reactions and far 
more prisonous and volatile than either. It is quite 
unknown to acie ce. On account of the importance 
of these bodies from the point of view of scien'ific 
jurisprudence, it will be necessary to carefully investi- 
gate the principal na.ive drugs and isolate and study 
the reacti in of their active principles. Until it has 
been do. c the toxic 'logical investigations required by 
the Law Courts will -.lways be a work of far greater 
difficulty and labour than is the case at Home. 
A number of anal.-es have been mad > of repre- 
sentative samples of soil from different parts of th ■ 
Colony with the primary view oi detenni ling the 
best method of a s ce tai dug the true value of the soil 
in contradistinction to the apparent value as shown 
by o diuary soil analyses. Tne distinction betwee i 
the two is enormous, for though an ordinary analyses 
may show the presence of 1 rge quantities of these 
constituents, which form the eal fertilising portion 
of the so I, yet only a minute fraction of tness m iy 
be i i a form available fi-om immediate p'ant food, 
bo that in leality the sri may b; exhausted. The 
Methods lob ad >pted for distinguishing b tweei these 
very different quantities require to be determined not 
only for e ch class of crop, bu what is more difficult, 
for each cdmate, as so much depends on the meteoro- 
logical conditions to which the soil is exposed. The 
determination of the absolute amount of each of tln-s 
essential soil con titumts si.ould he div ded into four 
cla ses: — (1). The quantity of each constitu nt iu- 
in dia ely available lor plant foo I. (2). The quantity 
of • ach readily cmertib'e into the j receediug form. 
(3) . The quantity of each which by i roper cultivation 
may be converted gradually into the pr ceeding classes. 
(4) . The quantity of each present in the unde- 
cmpo ed mineial and rocky constituen s from who e 
disintegration the true so I has arisen. Below a r e 
some of t ie remits obtai ed so far. Ea -h is founded 
on the moan of a number of fairly concordant analyses, 
showing that there is not so much difference in the 
compositi in of the soils in different portions of the 
principal districts in the Oj'ony. The analyses may 
be taken as giving t' e average composition of:— I. 
Tue black loam earths of the up country dist'icts. 
II. The brown shale oarths from th midland dis'ricts. 
III. The c ay sand oils from he uppjrco.st district-. 
IV. The greyish clay soils from t^e lower cjast 
districts. 
General Group Analysis 
I. 
II. 
III. 
IV. 
S ones 
... 5.32 
6.80 
2.50 
1.66 
Undeco nposcd rock 
... 10:88 
6. 0 
3.50 
8.10 
Sandy Constituents 
... 20.94 
13.68 
47. 12 
254.5 
Clayey Constituents 
... 42.50 
56.00 
3'i. 18 
46 '.11 
Calcare us Constituents 
8 88 
6.52 
8.40 
9 55 
Organic Matter 
... 7.48 
5.il8 
1.12 
3.78 
.Moisture 
... 4.55 
5.62 
2 88 
3.82 
Cjmplete Percentage 
Analyses. 
Sili a Alumina, ifcc. 
... 76.58 
78.J.6 
82.85 
77.70 
Iron Oxides, Sic. 
... 4.60 
5.15 
5 25 
I ;i i 
Lime, Magnesia, &c. 
... 3.87 
2 55 
1.76 
5.27 
l'otash, 8 ula, jfcc. 
... 2.12 
3.02 
2.04 
BUI 
Carbonic, sulphuric, &1. 
acid 2.68 
2.66 
1.43 
2.25 
Organic Matter... 
$4oiBture (free) 
... 7 48 
5.38 
4.12 
3.78 
... 3.27 
3.08 
2.55 
9.05 
I. II. III. IV. 
Percentages of Ultimately Available Constituents. 
Totod unavailable Cotisti- 
tueuts 
... 96.8) 
97 52 
98. 32 
97.61 
Lime 
... 1.15 
.87 
.46 
.78 
I'-tash 
.48 
.54 
.37 
.83 
Phosphoric Acid 
.12 
.08 
.03 
.11 
Organic Matter 
... 7.29 
.80 
.71 
.56 
Nitrogen ... 
.16 
.19 
.11 
.08 
Percentages of immediately available nonstitueuts. 
Lime ... ... .2s0 .141 .010 .125 
Pota h ... ... .110 .183 .102 .115 
I't'osphoric Acid ... .032 .012 .036 .010 
Nitrogen ... ... .041 .('30 .O'U .007 
The last division is of far less value than the other?, 
on account of the numbers varying so much in the 
case of each soil that it is scarcely possibl \ to properlv 
average them, and each soil would have to be judged 
on the basis of its own particular analysis. Tne pre- 
ceding r suits will be of interests for the s ka of 
comparison with corresponding analyses of represen- 
tative European soils. In addition, a number of 
anal. ses hav j been made of specimens of marls and 
sandy li nes'ones, with the vie -v of ascertaining how 
far they might be of value as a calcareous m.nnre 
for agricultural purposes, aud a somewhat smaller 
number of analyses of simples of pho j pliatie argil- 
laceous nodules o' " coi prolites," with the aim of 
determining their suitability for use as manure. 
Little use, however, has been made of the Govern- 
ment Laboratory for the purpose of promoting the 
agricultural interests of ths Co! uy, ye: much more 
might gradually be done ; n this dir. ction than has 
as yet been attempted. Much cannot be done by a 
single pair of hands, but one head ■ a-i direct many 
ha-ids, and it is easy and not expensive to increase the 
number f ha ids for performing the more mechanical 
work. The general idea is to establish a laborator , 
on a similar principle to those in o n ction with 
some of the agricultural societies, wiere in return for 
a small fee— the main expense being borne by the 
Gove nment — there could' be obtained the ordinary 
elementary an ilysis of soils, waters, feeding stuffs, and 
manures, such as commonly fall within the province 
ot a public analyst. But something else is required 
beyoud i lach g fa ilities at the disposal of the C olonial 
furmer for obtaining the ordinary description of ana- 
lyses. These are not sufficient, their use will only 
lead to disa- p i itmeut. and discourage agricu tnrist 
from availing themselves of the assistance of -the 
resources of science What then is wanted from 
science is : whether the soil comains an adequate 
■supply of those particular constituents wh ch are 
essential to p'ant life, and whether it con'ains a suf- 
ficient p oyo tion of these in a form immediately 
available for plant food, but also that it does not 
c nitain those other constituents which are harmful to 
p ant ife, or destructive of manures applied to the 
soil. This is th < province of chemical analyses. Put 
further it is essential that th<s soi should be in a fit 
physical condition for sustaining plant 'ife, a most 
important factor in a climate lik ■ that of South Africa, 
for however rich a soil may be, unl- ss its ph aieal 
properties »re favourable, it will yield only poor crips. 
This is the province of chemical physi s. Finally 
there comes the question whether the co stituents of 
the soil are are such as to enable it to steadi y supply 
the req drenients of the growing crop, not only with its 
mineral food but with its organic food, by maintaining 
the c ndition esseu ial for transforming the plant 
food from the state in which it exists in the soil 
into the firm under which it i- absorbed into the p ant 
system; and moreover, to supply it in ih order and 
varying proportions, which are necessary as the crop 
grows and ripens. It ia here that comes iu the wide 
theoretical knowledge of the sc entitle chemist and 
the practical experience of the billed agriculturist, 
together with that mo>t important factor, the jlli la- 
ment of the man of common sense. This is the 
information which agriculture has a right to expect 
from science Bat what are the conditions upon win ih 
this information is to be based? It shnu d be the 
business of the Government Chemist aud the work 
