It has been urged against this opinion that in some districts where coffee planting has proved a complete failure, dolomite is found most abundantly; but I have very little doubt that the dolomite here alluded to is only magnesian limestone, and which is most inimical to the coffee bush.

I am aware that already several manures have been tried on coffee with varying degrees of success.  Guano has, I believe, quite failed, and is besides very costly.  Cattle manure is said to be effective, and no doubt it is, but it is a costly and troublesome affair.  Bones, ground fine, are now being tried, though they cannot but prove most expensive, especially when imported.

    A ton of bone dust contains of animal matter, 746 lbs,; phosphates
    of lime, &c., 1,245 lbs.; carbonates of lime, &c., 249 lbs.

The virtue of bones lies in the phosphates far more than in the animal matter, and thus their action on soils is felt for many years after their application.  The Singalese cultivators of paddy about Colombo and Galle, appear to have been long aware of the fertilizing effects of this kind of manure, and import the article in dhonies from many parts of the coast:  they bruise them coarsely before applying them.

The partially decomposed husks of the coffee berry have been tried for some years, and successfully, but they are difficult of collection, and bulky to remove from one part of the estate to another.

In Europe it would appear that little is yet known as to the causes of the fertilising effects of oil cake:  some suppose them to arise mainly from the oil left by the crushing process, but this is not at all clear.  I do not, however, see that we must look for much assistance from Poonac as a manure for coffee:  for the cocoanut tree it is doubtless most valuable, but we have yet to learn that, beyond supplying so much more vegetable matter, it helps the action of the soil on the roots of the coffee bush, which, after all, is what is really required.

For the proper application of the dolomite to land as manure, it should be freely burnt in a kiln, with a good quantity of wood, the ashes of which should be afterwards mixed with the burnt lime, and the whole exposed for several days to the action of the air, sheltered of course from the weather.  The mixture should be applied just before the setting in of the monsoon rains:  if the land be tolerably level, the lime may be scattered broadcast on the surface, though not quite near the plants.  When the estate to be manured is steep, then the substance to be applied should be placed in ridges cut crossways to the descent of the slopes.

About one cwt. to the acre would be ample for most lands; some may, however, require more.  The contents of the husk pits might advantageously be mixed up with the burnt lime, when a sufficiency of it has been saved.

A planter in Ambagamoe states that he has tried the following remedy for that destructive scourge, the coffee-bug, with great success.