Supplement to the " Tropical AgfieuUurist.'' 
[Dec. 1, 1903, 
English potato in times of scarcity. As it is, 
supplies of the latter have to be drawn from 
France, Holland, Germany, Belgium, and even the 
Argentine and other places. In this connection, 
it is interesting to note that trial shipments of 
sweet potatoes have been made from the West 
Indies. 
The Agricultural News, Barbadoe?, points out 
that Cocoa canker — as the bark disease has come 
to be called — is not so new a disease as is generally 
thought, and quotes thus from Porter's Tropical 
Agriculturist (1833) : — " Cocoa trees aie likewise 
subject to a disease which shows itself in the 
form of black spots or blotches on the bark and 
which as soon as they appear should be carefully 
cut out, or the trees will quickly die." Verily, 
there is nothing new under the sun ! 
The Agricultural News, Barbadoes, gives the 
following analysis of sweet potato meal by Prof. 
Church : Water at 100° C, 12*9, ether extract (oil 
&c.) I-l, fibre 2*4, Nitrogenous matter (]N'=-584) 
3'7 (albuminoids coagulated by phenol-method 3'4), 
ash 2"4, starch, sugar, gum, &c. by difference 77'5, 
The sample was of meal prepared by Dr. Rat by 
the aid of machinery. 
The dried leaves of the screw pine are used 
in Dominica for making hats which are sold at 
tor 6d. to 1/6 each, according to quality of work- 
manship. In Ceylon the leaves of the wild date 
{Phoenix zeylanicum) take their place. 
The great disparity of price in Jamaica and 
Cochin ginger (in favour of the latter) is explained 
by the fact that the former lacks careful grading 
which tells against it, for buyers feel they can 
depend on Cochin ginger to be what the marks 
indicate, and prefer to purchase an article of 
known quality. It is authoritatively asserted that 
" Cochin ginger is actually of less value than 
Jamaica," and yet the London buyers will pay 
more for it ! 
The three best materials for use in storing 
sweet potatoes have— by actual trial— been found 
to be cotton seed hulls, dry sand, and cotton 
seed, in the order named. Storing in straw is 
condemned. 
We read in an exchange that Mr, Hoffmann 
Bang, a Dane, has erected machinery at St, 
Thomas, in the Danish West Indies, for the 
manufacture of dried banrnas for export ia closely 
packed handy cardboard boxes. 
The mosquito {Culex Pungens) is said by 
Dr. iL. O. Howard to have a minimum life- 
history period of ten days. In the case of small 
fruit flies (Drosophilila &c.) which attack fallen 
fruit t ,e life-history is even shorter, and some 
reared on a mango completed the cycle in eight 
days. . " 
rJ^/ i''^K'^'i^°"' '''^ or acids, here is a good 
recipj :— 1 lb. of ammonium chloride or sal ammo- 
mac finely powdered is very completely mixed with 
i v A ^r^"'^ °^ saltpetre and labelled 
n.d T„h '-J' , ^°Z^'' ^ ^''^ Scotch Soda 
^li S 1 2-" For use take' an 
equal break of No. 1. and No. 2, stir together, 
place in an ice poil round the vessel to be cooled 
and pour rather less cold water than is required 
to dissolve the whole. If, for instance, a quart 
of IN 0. 1 and No. 2 are taken, they will require about 
otie quart of water to dissolve them. The tem- 
perature will fall to about 30° b?loio "freezing 
point," which is the extent of cold required to 
freeze a liquid. The amount of water used is of 
the greatest inrportance, too much will consume 
the cold produced. The ice pail may be of wood 
but the vessel with the liquid to be frozen should 
be of pewter or other metal, and the mixture 
should surround the vessel nearly to the top. 
