But soon we had something to think of besides the view.  The tumultuous assemblage of dark, dense clouds, resting upon the river-surface in our rear, formed line or rather lines, step upon step, and tier on tier.  While the sun shone treacherously gay, a dismal livid gloom palled the eastern sky, descending to the watery horizon; and the estuary, beneath the sable hangings which began to depend from the cloud canopy, gleamed with a ghastly whitish green.  Distant thunders rumbled and muttered, and flashes of the broadest sheets inclosed fork and chain lightning; the lift-fire zigzagged in tangled skeins here of chalk-white threads, there of violet wires, to the surface of earth and sea.  Presently nimbus-step, tier and canopy, gradually breaking up, formed a low arch regular as the Bifrost bridge which Odin treads, spanning a space between the horizon, ninety degrees broad and more.  The sharply cut soffit, which was thrown out in darkest relief by the dim and sallow light of the underlying sky, waxed pendent and ragged, as though broken by a torrent of storm.  What is technically called the “ox-eye,” the “egg of the tornado,” appeared in a fragment of space, glistening below the gloomy rain-arch.  The wind ceased to blow; every sound was hushed as though Nature were nerving herself, silent for the throe, and our looks said, “In five minutes it will be down upon us.”  And now it comes.  A cold blast smelling of rain, and a few drops or rather splashes, big as gooseberries and striking with a blow, are followed by a howling squall, sharp and sudden puffs, pulsations and gusts; at length a steady gush like a rush of steam issues from that awful arch, which, after darkening the heavens like an eclipse, collapses in fragmentary torrents of blinding rain.  In the midst of the spoon-drift we see, or we think we see, “La Junon” gliding like a phantom-ship towards the river mouth.  The lightning seems to work its way into our eyes, the air-shaking thunder rolls and roars around our very ears; the oars are taken in utterly useless, the storm-wind sweeps the boat before it at full speed as though it had been a bit of straw.  Selim and I sat with a large mackintosh sheet over our hunched backs, thus offering a breakwater to the waves; happily for us, the billow-heads were partly cut off and carried away bodily by the raging wind, and the opened fountains of the firmament beat down the breakers before they could grow to their full growth.  Otherwise we were lost men; the southern shore was still two miles distant, and, as it was, the danger was not despicable.  These tornadoes are harmless enough to a cruiser, and under a good roof men bless them.  But H.M.S.  “Heron” was sunk by one, and the venture of a cranky gig laden a fleur d’eau is what some call “tempting Providence.”

Stunned with thunder, dazzled by the vivid flashes of white lightning, dizzy with the drive of the boat, and drenched by the torrents and washings from above and below, we were not a little pleased to feel the storm-wind slowly lulling, as it had cooled the heated regions ahead, and to see the sky steadily clearing up behind, as the blackness of the cloud, rushing with racer speed, passed over and beyond us.  The increasing stillness of the sea raised our spirits;