49^ THF TROPICAL AGRIOULTURISt. [January i, 1891. 
4. Tobacco : This insiduous narcotic is valuable in 
the destruction of plant-lice, mites, &o. Applied as a 
powder or by its fumes it often is quite beneficial. 
Bisulphide of carbon, like chloroform, is highly 
volatile, but its vapour, unlike that of chloroform, is 
Very explosive. Bins aud corn cribs can be easily rid 
of auts, weevil, rats, mice, beetles, &c., if the room be 
made air-tight, and occasionally filled from the top 
with the vapour of bisulphide of carbon. This is the 
only way in which our farmers ever will keep corn, 
peas, &c., from insect attacks. 
Of course kerosene and such arsenical poisons as 
Paris green and London purple are ohemioally active, 
but for the destruction of green bugs, if we were 
troubled with the pest, we should feel much inclined 
to try a decoction of gum leaves and mana grass, 
brought up to a sticky consistency by mixing 
starch or flour, gum, clay and lime, with some 
sulphur added. If a covering of this stufi were 
applied to the green bugs in dry weather and 
left on for a few days, I believe the parent scales 
and their enclosed progeny would be smothered 
to death and come oS in flakes with the prepara- 
tion. If inclined to stick, the application and the 
insects could be washed off, with water, or a decoc- 
tion of gum leaves or coarse lemon grass. 
In Australia the fruit growers have other enemies 
than insect or fungoid pests to contend with. 
One authority states that birds, including the 
improved sparrow, are still worse, insectivorous 
birds often feeding on friendly insects, such 
as the mantis. Imported hares, too, are 
hurtful, but most destructive of all are perfect 
clouds of the large frugiverous bat known as “the 
flying-fox,” which are so cunning that it is diffi- 
cult to lessen their numbers by powder and shot 
or even dynamite. Neither birds nor bats, I believe, 
have ever been known to meddle with coffee berries, 
on which however, monkeys and jackals have been 
known to feed, while the jungle rats in one year 
destroyed £10,000 worth of coffee in the region 
whence I write. Bandicoot rats have occasionally 
rooted up a few tea trees ; but, on the whole, it 
is seldom that so large an expanse of one cultivation 
as the tea fields of Ceylon compose has been so 
little affected by injurious animals, birds, insects 
or fungi. Long may this happy immunity continue 1 
he dii'feeence in the bainfall at the beginning 
and the end op novembee — the rainfall at 
NUWAKA ELIVAj HAKGALA AND ABBOTSFORD AND OF 
OTHER PLACES— EXPLANATION OF DIFFERENCES IN 
RAINFALL — VARIATIONS IN MEAN TEMPERATURE AND IN 
MAXIMUM AND MINIMUM SHADE TEMPERATURE— Hi- AT 
IN THE SUN— NOCTURNAL RADIATION — CEYLON “ PEAT” 
— THE ALLEGED DISCOVERY OP BITUMINOUS COAL 
AND ANTHRACITE ON ROTHSCHILD ESTATE — HOW TO 
TREAT PEATY SOIL— EFFECTS OF A HAILSTORM ON TEA 
AND CINCHONA — HAIL IN INDIA AND OTHER COUNTRIES 
— CAUSES OF HAIL — CHANGEABLE WEATHER. 
Nanuoya, Dec. 1st, 
This morning 1 mentioned the contrast between 
the early portion of November, when we were all 
asking “What has become of the north-east mon- 
soon ? ” and the latter portion, of the month during, 
which the answer has been emphatically given in 
the shape of thunder-and rain-storms, with occasional 
semi-gales of wind. The figures for rainfall and rainy 
days will show how striking the contrast has been. 
From Nov. 1st to the 16th, rain fell only on 6 days 
and on three of these the measurements were 
only 5 cents on 2 days and 2 cents on 1, the total for 
the 16 days being only 75 cents of an inch. From 
the 17th to the 3Uth, on the other hand, the rainfall, 
on 11 days has been 8'BO inches, 5 out of the 11 
rainy days giving such storm quantities as 1-38, 
1-47, 1-36, 1-4B, and yesterday 2-Oy. This latter 
buret sent Iho rainfall of November up to T56 
against a 7 years’ average of 7-37 ; the total for 
the 11 months of the year being 85-93, against 
an average of 84-32. We are thus 1-61 inch above 
our average quantity, while our rainy days num- 
ber 190 against 192. Unless, therefore, December 
turns out an abnormally rainy month, we are 
likely in 1890 to realize very closely our 7 years’ 
annual average of 92-11 inches of rainfall on 209 
days : only slight rain falling on fully one fourth of 
the number. At an elevation of about 5,800 feet and 
facing the south-west, this gives us 5-14 inches 
more than Hakgala (altitude 5,581 and facing the 
north-east) receives and 5-95 less than is deposited 
at Nuwara Eliya, which is situated between the 
two monsoons, at an elevation of 6,240 feet above 
sea-level. The averages of the three mountain 
stations are : — 
Nuwara Eliya 6,240 feet 98-06 inohes; 
Hakgala 5,581 „ 86 97 „ 
Abbotsford 5,800 „ 92-11 „ 
There is here a graduation according to elevation, 
but the principle by no means holds generally g ood 
the river valleys below the three stations getting 
from 100 to 150 inches of rain, while the ranges 
which face the south-west monsoon, at an eleva- 
tion of 3,000 to 4,500 feet, get 200 inches up to 
250. Theberton estate, Maskeliya, with an annual 
average of 217 inches, is only 3,315 feet above sea- 
level, while Padupola, believed to be the rainiest 
station in Ceylon, is still lower down. The region 
round about Nuwara Eliya, protected from the 
extreme moisture of the south-west monsoon vapour- 
clouds by the Adam’s Peak ranges, is fortunate in 
enjoying the happy mean for tea cultivation of 100 
inches down to 80. Even 70, well distributed, suits 
this most cosmopolitan of plants. 
The disproportion of rainfall to elevation is 
easily explained by the relative positions of moun- 
tain ranges to the course of the sea-vapour- 
laden monsoon winds, but it is not so easy to 
understand the varying rate at which mean temper- 
ature decreases with varying altitudes. The differ- 
ence of level between the observatories at Colombo 
and Nuwara Eliya is 6,200 feet (the Colombo 
observatory being 40 feet above mean sea-level), 
and the reduction of mean temperature, in pro- 
portion to ascent, is from 80-7 at the sea station 
to 57-7 in the mountain sanatorium, a fall of 
23 degrees, or 1 degree for every 269 feet of alti- 
tude. This fairly agrees with the formula we have 
seen in books on meteorology. But when we 
come to compare Colombo with Hakgala at 5,581 
feet, with a mean temperature of 61-2, the reduction 
of temperature is only 19 5, or 1 degree for each 
291 feet. The higher temperature in this ease, 
compared with Nuwara Eliya, apart from differ- 
ence of elevation, may be due to the fact that the 
great isolated mountain is densely forested, and faces 
the warm valley of Uva? But Badulla, 2,225 
feet altitude and 72-8 mean temperature, is in 
that warm valley, and yet the reduction of 
temperature, as compared with Colombo, is in this 
case 8 degrees, or a fall of 1 degree for every 273 
feet. Very different indeed is the case of Kandy, 
elevation 1,696 feet and mean temperature 75-9. 
This is only 5 degrees lower than Colombo, or 
only a fall of 1 degree in 332 feet, against 269 in 
the case of Nuwara Eliya. Can this great difference 
be due to the sheltered position of Kandy and -the 
heat of the sun reflected,, during the day, from the 
white, quartzy sand of the roads and the undarkened 
whitewash of the houses? The differences, hitherto, 
in the rate of depression for altitude have not 
been excessive, but we are utterly puzzled when 
we come to compare Badulla with Kandy. For 
an elevation higher by only 529 feet, the fall in 
