July i, 1891.] 
THE r^Of^lCAL AGRICULTURIST, 
59 
; Your oorreaponilent " W. B. L." secured his tubers 
from "Comilla" a few years back, since which he lias 
kept up its cultivation which aa he says is rather 
expensive wantiug a good prepared soil with plenty 
of manure. I also got anotber gentlpmau, an ofBoial, 
to cultivate it on his property at Hewagam Ko^ale, 
but I am afraid this gentleman hus given it up and 
has confined his attenti m only to coconuts and popper, 
the latter of which he 6rm!y believes in aa paying 
handsomely. I remember sending a few specimens 
of the yam to your office end the then editor was 
pleased to fay after trial that it was equal to or 
even superior to the best Jaffna. I say so as well 
nnhesitatirigly, and would stiongly aiviae you to 
procure some specimens from your vforthy correspon- 
dent "W. B. L." when you will endorse my opinion. 
HORTICULTURIST. 
OVEE-PRODUCTION OF TEA. 
Sib, — Referrins; to what H. E. the Governor 
said at the Dimbula breakfast, reapeoting over pro- 
duotion being the chief danger tea planters need 
fear, would it not be well, before the danger 
comes too near, for all tea planters to combine 
and push their teas in countries where they are 
now little known, notably on the continont of Europe 
and in Australia ? 
It would greatly strengthen the hands of the 
" Oeylon Tea Fund " if all planters would join 
and give 37 cents per 1,000 lb, of green leaf, 
whioh I am wiilUig to do for aa long as may 
be necessary if my brother planters will do the same. 
Please give my name and address to any en- 
quiring persons, — Yours truly, 
PROPRIETOR. 
OUR COCONUT SOILS. 
Dear Sir, — Not being a learned soientist myself, 
I am obliged to take such scraps o£ science as I 
need at second hand, but I am somewhat nice 
about the authorities I consult — applying only to 
Buoh as have made a name and position in their 
own branch of investigation. When B. assumed 
that silica was deficient in certain coconut fiei.is 
I applied to Professor Geikie, who gave me the 
following information : — More than one half of the 
earth's crust consists of silicate ; it is an essential 
element in all igneous rocks, from whioh all sedi- 
mentary rocks and soils are ultimately derived ; it 
is therefore not only abundant but everywhere 
present. lu regard to the agricultural value of 
silica, the following sentence from a recently 
published article by Professor Johnstone disposes 
of that question : — 
" Now silica and silicates are decidedly injuri- 
ous to all vegetables doubtless, but in particular 
to agricultural plants, I say injurious ; the time 
has gone past for considering silica an essential, 
a useful or even an innoxious accessory," 
OLD PLANTER. 
[We suppose it is our correspondent who quotes 
Professor Johnstone's dictum which certainly sur- 
prises us. One-half the crust of the earth com- 
Tposed of a substance which is noxious and only 
noxious to agricultural plants I " Cinnamon sand " 
is about 98 per cent silica, and yet the finest 
cinnamon in the world grows in such sand. — 
Ed, T. a.] 
CACKLING OF JUNGLE HENS. 
Adampan, May 19th. 
Bib, — Re. cackling of jungle hens, I am afraid I am 
rather late, but yet, shou'd you deem the following 
of any iaterest, they are at your disposal. 
I have had the opportunity of observing or rathei" 
I made it a point of studying the manners and ways 
of wild animals in general, and the question now at 
issue has been one of them, I could say from my 
own knowledge that the jungle hens do not cackle 
after lying. They have four peculiar notes :— one 
when they fly alarmed, one when they feed with the 
cook in reply to call, one when calling the chickens, 
one warning the chicks: the latter three similar to 
the domestic hen but in a softer key. The jungle 
hens lay more than four eggs ; I have taken as many 
as nine and I have seen a brood of eight chicks. 
I have never heard a jungle hen cackle and the 
cook replying in a similar key, as among tie 
demestio fowls. The onok when singing out hia 
" George Joyce " flaps his wings nearly like to his 
domestic cousin. — Yours truly, 
K. Dii HOEDT. 
THE CHEMISTRY OU' SOILS. 
Veyangoda, M\y t9th. 
DEiu 3i.^, — I cfiaiiot say with " Old Pluntei '' ciiat 
I am a leamed soieutisi,, ' for 1 :ay ,io pi-eten- 
tiona 'leing a scientist at all, whether learued 
or unlepvned. Ltte hiiu the information I get ou 
sciencilic subjects 'S from bookc ; but I do not enjoy 
the same nrivjlef;ef as he tlie choice of my atilhor'- 
ties. Blv (tuthorities •»rp. EUe oi-diuarj i,e^i books 
that CH,ii he ■nurciiasftM > the ooo^^-stotd at iht Observer 
Office. A vei" anp etpjtiou,', booK h- Aitied -ibsoa 
xives ?i-ec!tiely Cue same iufo .:tiaL un oj siUc as Pro. 
fesso'.' ©e;ti -J itOH^. -'-^Sihcs s ibe predoiiiaating coa- 
stitueni; o- iuosl st -^s, ;ockf, anu minerals; it is the 
ri?03t abundaTi lO' jiateria' o'' lue earth.'' My old 
friend has (iul i to che nunecesja y t: onhle of 
cou6ultnig sui;ii 111. '10 'li es "m liave ande a name 
and position ,_i i-oe ■ ih o^'auc*' of invest. gatiOn," to 
lefute astatemei.c o .illes^atiou t uid noo make. It ia 
theold j<aTne ol li}^ >« 'i -uan of jack ara, o.' oneV owa 
creation. Tbe Kls'.djuen. wbloli a '.s ''le^etf I made 
occurs in the fi sr o' my Ute s or. sa'i, wi/e' I say 
ih&t I h--",' dea t le aess ina,. the eason pi yooco- 
L.ut trees c.orr,^ ay.^ij jaiinot sui.ijOi-t tueu' ',',1; 
bu'jches "iiijy be oiv . i,(r ■ defioieijcT o' s ''oa." 
A little lijOiM -.L <Kijn'c luve vifsfied '■ O'r) Pia.ite.; " 
that 1 ooitlu lui .J0^■- >■ -lie to \ d'^'icienc/ of 
silica i)' tiie ^oi )ui j .a? comnosH.O'i 3^ lUo .ree, 
for I .-iiaLeo over a/ni j i i^aiu una^ out Oi: ■ 
properties of «slt 's 'it l ' / to rea',c,- ■soh'U'.e tW'i 
silica lu ttie aoil, '.'C -.oi a s.'.j,i,\/ u lO ine <oii. I 
hold to the oere' ,u. v ■.ifi' - ter<u!. .o lOi'.ecea -"id 
stifTen vegetable I'S^res, Ovvmf, .0 ilie sitiw uf 
wheat contaiu^us; coi>' i;«: ■vb' • ovev oO Dti ee it of 
silica, it was fci Iod^ iO''M 't ,6d ibii. ioi't miuaral 
was absy'ute'.y n6Ceg'ia.''y u lUe lO^I lo; i.o ?.>■ ■•v»ih 
and that it '^.ivt ■stiffness tc the -ica--'. Receij ej;- 
peuments ai frowiui whest oa si soii -ievo d 3l - Uoa 
have disproved ihis upJ'tif. U.: iimil Wo:'i too aon- 
ducted some e;:pe -irueut.s i'j i,se same Jii ectiou, and 
his vpfilict wns ibal .)io '. Ice. was not ludis- 
pensabie for plo'i. -no yet ihe « ,fOrpnon of dlioa 
greal'y aasisteil bie is.s. ai latio i ol otbei plMi',. iood, 
and that p'KQt? U> v. u.C" -I'lMn ^^^s lupphed ■stowed 
better developMitn'i .aau ino.-ie witiiom jC. Now I 
contend that I Have Mf^r ai'ibsiii.v o: th" oelie' I 
hold. AU eii^arer. 'n ,i,<;ricii' ura'. •■..snits la've 'aily 
experience af ine li"''-? ence betwae/i che poge. bilit y 
of mR^in^ a pro.JaCu ';row .in.i growing >t ,iito a 
hea'thv r.au wei lieveVpeci ^pecnen. Tin- itj^'ifeaoe 
is thttb ue\,weeu Jw ^^ow ji.: >" :•. prounci' g a Joss 
and 1 ofit. lie'^i'lu." lU k .o my Ihi.ij^tJg the 
esperimeuvb oul_v went iiO pcove tli.^t ■■ uca ^as not 
essential to llie >;rowlh of whea^ ; they went no 
furthej . 
And non t come to the jecoad pa b ct the letter 
of " Olu Plame.' ere tie quotes with approval the 
dictum of V^oinssor Jou n,.s,one. t may remark en 
passani thai 1 iaice it, for gianted that " Alesaade' 
J diustone'' 1'- a ProfgHBOf solely on '■ CM Piantets' ' 
amlhority, for thou>;h it may display my ignorance of the 
names of the shining Jighta of the scientific worldi yet 
