Dfc. I 1893,] THE TROPICAL AGRICULTURIST. 37^ 
of the thermometer accompanying Ahel's test 
apparatus, so that the flashing point had to be' 
(leterniined by the open test and ^vas found to be 
260" F. The firing point or the temperature at 
which the oil became permanently ignited was 
ol r F. The specific gravity of this oil at 82° F 
was '82, and its viscosity, compared with 
American kerosene >\ as as 30 to 20. 
The following is a comparison of the gravities 
and flash points of the four princi])al mineral oils 
used as illuminants in Europe : — 
Specific Flash 
gravity. point. 
Ordinary Anieii<-au petroleum '790 73° F. 
Americ-an ■■ Fioyal ihylight " -SIO 76° 
Ttussian 2") 82° 
j^ootch extra refined -809 104° 
Lithrii-atiiiq Oils. 
Mineral oils of liigli Hashing ])oiut are used in 
f'eylon, as elsewhere, as lubi iciuing oils. Such 
oils sometimes have fanciful nanies, but they are 
prepared from petroleum or shale. According to 
Allen " mineral lubricating oils have densities 
" ranging from -850 to •915, the most usual 
" gi'avities falling between -880 and •905. Mineral 
" lubricating oils boil at a very high temperature. 
" The Hashing point of the pale Scotch oils from 
" shale range from 1.30° to 180° C (266° to 356° F.), 
" and of the darker oils and greases fioni 180° to 
" 23^1° C. (356° to 446° F.). The viscosity at 15° C. 
" (59° F.) is from 2 to 7 times that of water-"' 
Most of the mineral oils exhibit the character 
of Ituorescenee, and they are not saponifiable ; 
characteristics whicii ai'e useful in enabling us 
to distinguish them from fat oils. 
The following series of propositions give in a 
condensed form a description of tiie properties of 
luliricating oils. They are from Spon's " Encyclo- 
pfedia of the Industrial Oils ' with some verbal 
alterations by Allen. 
(f) "A mineral oil Hashing below 150° C is 
unsafe. 
(/') A mineral oil losing more than 5 i)er cent 
in ten hours at 15 !o20°C. is inadmissible, as the 
evaporation creates a viscous residue, or leaves 
the bearing dry. 
(c) The most fluid oil that will remain in its 
place fulfilling otlier conditions is the best for all 
light bearings at high speeds. 
[d) The best oil is that which Iihs die greatest 
adhesion to metallic surfaces, and the least 
cohesion in its own particles ; in this respect the 
fine mineral oils stand 1st ; sperm oil, 2nd ; Neat's 
foot oil ?rd ; and laid oil, 4th ; consequently, 
the finest mineral oils are best for light bearings 
and high velocities, the best animal oil to give 
body to fine mineral oils is sperm oil (';) ; lard 
;ind Neat's foot oils may replace s[ierm oil when 
greater tenacity is re<iuired. 
(>') The hest mineral oil for cylinders is one 
haviiiora density of -893 and a flashing |)oint of 360° C. 
(/') The best mineral oil for hea\ y machinery 
has a density of •SSO and a Hashing point of 269° V. 
iff) The I)est mineral oil for light bearings and 
high \ elocities has a density of 871, and a flashing 
[loiiit of 262 ( '. 
(/() -Mineral oils alone are not suited for heavy 
machinery, on account of their want of body ; but 
well jiuiilied animal oils are a])|dicable to the 
llea^• ies t m ac h i 1 1 e ry . 
{/) ()liv(i oil stands first among vegetable oils, 
.as it can be inirilied without the aiil of mineral 
acids. The (»ther \ egetablc oils which, thongli far 
inferior to oli\ e oil, are admirable as lubricants, 
are, in their order of merit, sesame, earthnut, 
rape and ctd/a, and cotton seed oils. 
(/) No oil is admissible which has been pun 
fied by means of mineral acids." 
The property of lubricating oils called viscosity, 
which is determined by noting the number of 
seconds a given measure of oil takes to run through 
a small orifice of definite size, is one which varies 
much according to temperature, but does not vary 
in any definite manner according to the specific 
gravity of the oil. In England the \iscosity of 
the commoner animal and vegetable lubricating 
oils varies though .a very wide range ; in Ceylon 
the range is much less, wliile above 80° C there 
is very little dift'erence in this respect between 
them. The following table quoted by Allen from 
a pamphlet by Messrs. J. Veitch, Wilson & Co. 
gives the viscosity for the commoner animal and 
vegetable lubricating oils for three temperatures. 
Kind of Oil. 
Sperm oil 
Olive oil 
Lard oil 
Rape oil 
Neat's foot oil 
Tallow oil 
Engine Tallow 
No. of Seconds. 
at 60° F. 
= l5-o°C. 
47 
92 
96 
108 
112 
143 
Solid 
at 120° F. 
= 49° C. 
30i 
37 
38 
4H 
37 
41 
at 180° F. 
= 82° C. 
25.3: 
28i 
28^ 
30 
29J: 
25 
2QI 
The author has not had occasion to test lubris 
eating oils as used in Ceylon. The following, 
howe\^er, are notes of a few obser^'ations made : — 
Luhricatinf) Oils used in Ceylon. 
The following are some of the lubricating oil- 
used for machinery in Ceylon : — 
Crane's Blachinern oil for machinery generally. 
This oil lias a greenish yellow color when seen by 
transmitted light, with a blueish green fluorescence 
or bloom when seen by reflected light. Its specific 
gravity at the ordinary temperature of Colombo, 
compared with water at che same temperature 
is •9.33. Crane's Patent OU for engine cylinders is 
reil by transmitted light Avith blueish green 
fluorescence and specific gravity •915. Rangoon 
oil used for machinery, gearing &c. is dark red by 
transmitted light with dark fluorescence .specific 
gravity '934. Enf/lehrrt's-oil, a dark-colored oil, used 
for engine cylinders, valves &e. Castor oil of lemon 
yellow color, specific gravity ^965 ; and also Coconut 
oil are used as lubricants, though they are less 
in favour than formerly. Coconut oil contains 
free acids which is a disadvantage in a lubncating 
oil. The mineral lubricating oils of ^Messrs. 
Thompson and Bedford Company, Limited, of New 
York, are also used to a considerable e.xtent in 
Ceylon. In specific gravity they range from '880 
to ^930 at standard temperature. 
Fixed Vegetable Oils. 
As examples of Ceylon fixed vegetable oils 
might be mentioned Coconut oil, Gingelly oil, and 
Margosa oil. 
Coconut Oil. 
The oil is obtained from the dried kernel of the 
roros-inirifrra, technically known as C()i)ra, either 
by the process of boiling in water, and skimming 
oil' the oil, which rises to the surface, or, moie 
commonly, by pressure. Its uses are very varied. 
It is used for burning, either in its cniile state a-s 
in warm countries, or after being converted into 
candles as in cold countries. It is largely used in 
Eastern cookery ; also as a cosmetic. The manu- 
facture of -soaps also absorbs a large iiiiantity of 
