A long-legged mule, after gibbing enough to satisfy his own self-respect, condescended to trot off with us up the tramway, which lay along a green drove strangely like one in the Cambridgeshire fens.  But in the ditches grew a pea with large yellow flower-spikes, which reminded us that we were not in England; and beyond the ditches rose on either side, not wheat and beans, but sugar-cane ten and twelve feet high.  And a noble grass it is, with its stems as thick as one’s wrist, tillering out below in bold curves over the well-hoed dark soil, and its broad bright leaves falling and folding above in curves as bold as those of the stems:  handsome enough thus, but more handsome still, I am told, when the ‘arrow,’ as the flower is called, spreads over the cane-piece a purple haze, which flickers in long shining waves before the breeze.  One only fault it has; that, from the luxuriance of its growth, no wind can pass through it; and that therefore the heat of a cane-field trace is utterly stifling.  Here and there we passed a still uncultivated spot; a desolate reedy swamp, with pools, and stunted alder-like trees, reminding us again of the Deep Fens, while the tall chimneys of the sugar-works, and the high woods beyond, completed the illusion.  One might have been looking over Holm Fen toward Caistor Hanglands; or over Deeping toward the remnants of the ancient Bruneswald.

Soon, however, we had a broad hint that we were not in the Fens, but in a Tropic island.  A window in heaven above was suddenly opened; out of it, without the warning cry of Gardyloo—­well known in Edinburgh of old—­a bucket of warm water, happily clean, was emptied on each of our heads; and the next moment all was bright again.  A thunder-shower, without a warning thunder-clap, was to me a new phenomenon, which was repeated several times that day.  The suddenness and the heaviness of the tropic showers at this season is as amusing as it is trying.  The umbrella or the waterproof must be always ready, or you will get wet through.  And getting wet here is a much more serious matter than in a temperate climate, where you may ride or walk all day in wet clothes and take no harm; for the rapid radiation, produced by the intense sunshine, causes a chill which may beget, only too easily, fever and ague not to be as easily shaken off.

The cause of these rapid and heavy showers is simple enough.  The trade-wind, at this season of the year, is saturated with steam from the ocean which it has crossed; and the least disturbance in its temperature, from ascending hot air or descending cold, precipitates the steam in a sudden splash of water, out of a cloud, if there happens to be one near; if not, out of the clear air.  Therefore it is that these showers, when they occur in the daytime, are most common about noon; simply because then the streams of hot air rise most frequently and rapidly, to struggle with the cooler layers aloft.  There is thunder, of course, in the West Indies, continuous and terrible.  But it occurs after midsummer, at the breaking up of the dry season and coming on of the wet.