- The Alabama on the Indian Ocean
-- the passengers questioned, and contracted with
-- the Agulhas current
-- the ‘brave West winds’
-- a theory
-- the Islands of St. Peter and St. Paul
-- the tropic of Capricorn
-- the South-East trades and the monsoons
-- the Alabama arrives off the Strait of Sunda, and burns one of the ships of the enemy
-- runs in and anchors under the island of Sumatra.
When Bartelli awakened me, at the usual hour of ‘seven bells’—half-past 7 A. M.,—on the morning after the events described in the last chapter, the Alabama
was well launched upon the Indian Ocean
She had run the Cape of Good Hope
out of sight, and was still hieing off before the gale, though this had moderated considerably as she had run off the coast.
We were now about to make a long voyage, tedious to the unphilosophical mariner, but full of interest to one who has an eye open to the wonders and beauties of nature.
My first duty, upon going on deck, was to put the ship under sail, and let the steam go down; and my second, to have an interview with the ‘passengers,’ who had come on board, overnight.
We were now on the high seas, and might, with all due respect to Queen Victoria, put them under contract.
If the reader recollects Falstaff
's description of his ragged battalion, he will have a pretty good idea of the personnel
I had before me. These subjects of the Queen
stood in all they possessed.
None of them had brought any baggage on board with them.
Ragged blue and red flannel
shirts, tarred trousers, and a mixture of felt hats and Scotch caps, composed their wardrobe.
Their persons had passed muster of the surgeon, it is true, but it
was plain that it would require a deal of washing and scrubbing and wholesome feeding, and a long abstinence from ‘drinks,’ to render them fit for use. Upon questioning them, I found that each had his cock-and-a-bull story to tell, of how he was ‘left’ by this ship, or by that, without any fault of his own, and how he had been tricked by his landlord.
I turned them over to the first lieutenant
, and paymaster, and they were soon incorporated with the crew.
I hold that her Majesty owes me some ‘boot,’ for the ‘swap’ I made with her, on that remarkable moonlight night when I left the Cape.
At all events, I never heard that she complained of it.
I was grieved to find that our most serious loss among the deserters, was our Irish fiddler.
This fellow had been remarkably diligent, in his vocation, and had fiddled the crew over half the world.
It was a pity to lose him, now that we were going over the other half.
When the evening's amusements began, Michael Mahoney
's vacant camp-stool cast a gloom over the ship.
There was no one who could make his violin ‘talk’ like himself, and it was a long time before his place was supplied.
I we felt convinced he had not been untrue to us—it was only a ‘dhrop’ too much of the ‘crayture’ he had taken.
For the first few days after leaving the Cape, we ran off due south, it being my intention to seek the fortieth parallel of south latitude, and ran my easting down on that parallel.
As icebergs have been known to make their appearance near the Cape in the spring of the year, I ordered the temperature of the air and water to be taken every hour during the night, to aid me in detecting their presence.
We did not discover any icebergs, but the thermometer helped to reveal to me some of the secrets of the deep, in this part of the ocean.
Much to my surprise, I found myself in a sort of Gulf Stream; the temperature of the water being from three to five degrees higher, than that of the air. My celestial observations for fixing the position of the ship, informed me at the same time that I was experiencing a south-easterly current; the current bending more and more toward the east, as I proceeded south, until in the parallel of 40°, it ran due east.
The rate of this current was from thirty to fifty miles per day. This was undoubtedly a branch of the great Agulhas current.
If the reader will inspect a map, he will find that the North Indian Ocean
is bounded wholly by tropical countries—Hindostan
, and Arabia
to the Red Sea
, and across that sea, by Azan
The waters in this great bight of the ocean are intensely heated by the fervor of an Indian and African
sun, and flow off in quest of cooler regions through the Mozambique Channel
Passing thence over the Agulhas Bank
, which lies a short distance to the eastward of the Cape of Good Hope
, they reach that Cape, as the Agulhas current.
Here it divides into two main prongs or branches; one prong pursuing a westerly course, and joining in with the great equatorial current, which, the reader recollects, we encountered off Fernando de Noronha
, and the other bending sharply to the south-east, and forming the Gulf
Stream of the South Indian Ocean
, in which the Alabama
is at present.
What it is, that gives this latter prong its sudden deflection to the southward is not well understood.
Probably it is influenced, to some extent, by the southerly current, running at the rate of about a knot an hour along the west coast of Africa
, and debouching at the Cape of Good Hope
Here it strikes the Agulhas current at right angles, and hence possibly the deflection of a part of that current.
But if there be a current constantly setting from the Cape of Good Hope
to the south-east, how is it that the iceberg finds its way to the neighborhood of that Cape, from the south polar regions?
There is but one way to account for it. There must be a counter undercurrent.
These bergs, setting deep in the water, are forced by this counter-current against the surface current.
This phenomenon has frequently been witnessed in the Arctic seas
. Captain Duncan
, of the English
, in describing one of his voyages to Davis' Strait
, thus speaks of a similar drift of icebergs:—‘It was awful to behold the immense icebergs working their way to the north-east from us, and not one drop of water to be seen; they were working themselves right through the middle of the ice.’
Here was an undercurrent of such force as to carry a mountain of ice, ripping and crashing through a field of solid ice. Lieutenant De Haven
, who made a voyage in search of Sir John Franklin
, describes a similar phenomenon as follows:—‘The
iceberg, as before observed, came up very near to the stern of our ship; the intermediate space, between the berg and the vessel, was filled with heavy masses of ice, which, though they had been previously broken by the immense weight of the berg, were again formed into a compact body by its pressure.
The berg was drifting at the rate of about four knots, and by its force on the mass of ice, was pushing the ship before it, as it appeared, to inevitable destruction.’
And again, on the next day, he writes:—‘The iceberg still in sight, but drifting away fast to the north-east.’
Here was another undercurrent, driving a monster iceberg through a field of broken ice at the rate of four knots per hour!
When we had travelled in the Alabama
some distance to the eastward, on the 39th and 40th parallels, the current made another curve—this time to the north-east.
If the reader will again refer to a map, he will find that the Agulhas current, as it came along through the Mozambique Channel
and by the Cape of Good Hope
, was a south-westerly current.
It being now a north-easterly current, he observes that it is running back whence it came, in an ellipse!
We have seen, in a former part of this work, that the Gulf
Stream of the North Atlantic
performs a circuit around the coasts of the United States
, the British Islands
, the coasts of Spain
, the African coast
, and so on, into the equatorial current, and thence back again to the Gulf of Mexico
From my observation of currents in various parts of the world, my impression is, that the circle or ellipse is their normal law. There are, of course, offshoots from one circle, or ellipse, to another, and thus a general intermingling of the waters of the earth is going on—but the normal rule for the guidance of the water, as of the wind, is the curve.
As we approached the 40th parallel of latitude, my attention was again forcibly drawn to the phenomena of the winds.
The ‘Brave West Winds’—as the sailors call them—those remarkable polar trade-winds, now began to prevail with wonderful regularity.
On the 30th of September, we observed in latitude 39° 12′, and longitude 31° 59′. The following is the entry on my journal for that day:—‘Rough weather, with the wind fresh from the N. N. W. with passing rain-squalls.
Barometer 29.47; thermometer, air 55°, water 58; distance run in the last twenty-four hours, 221 miles. Weather looking better at noon. The water has resumed its usual deepsea hue. [We had been running over an extensive tract of soundings, the water being of that pea-green tint indicating a depth of from sixty to seventy-five fathoms.] In high southern latitudes, in the Indian Ocean
, the storm-fiend seems to hold high carnival all the year round.
He is constantly racing round the globe, from west to east, howling over the waste of waters in his mad career.
, his labors are never ended.
He not only does not rest himself, but he allows old Ocean none, constantly lashing him into rage.
He scatters the icebergs hither and thither to the great terror of the mariner, and converts the moisture of the clouds into the blinding snow-flake or the pelting hail.
As we are driven, on dark nights, before these furious winds, we have only to imitate the Cape Horn
navigator— “tie all fast, and let her rip,” iceberg or no iceberg.
When a ship is running at a speed of twelve or fourteen knots, in such thick weather that the look-out at the cat-head can scarcely see his own nose, neither sharp eyes, nor water thermometers are of much use.’
These winds continued to blow from day to day, hurrying us forward with great speed.
There being a clear sweep of the sea for several thousand miles, unobstructed by continent or island, the waves rose into long, sweeping swells, much more huge and majestic than one meets with in any other ocean.
As our little craft, scudding before a gale, would be overtaken by one of these monster billows, she would be caught up by its crest, like a cock-boat, and darted half-way down the declivity that lay before her, at a speed that would cause the sailor to hold his breath.
Any swerve to the right, or the left, that would cause the ship to ‘broach to,’ or come broadside to the wind and sea, would have been fatal.
These ‘brave west winds,’ though thus fraught with danger, are a great boon to commerce.
The reader has seen how the currents in this part of the ocean travel in an ellipse.
We have here an ellipse of the winds.
is hurrying to the Far East
, before a continuous, or almost continuous north-west gale.
If she were a few hundred miles to the northward of
her present position, she might be hurrying, though not quite with equal speed, before the south-east trades, to the Far West
We have thus two parallel winds blowing all the year round in opposite directions, and only a few hundred miles apart.
Storms are now admitted by all seamen to be gyratory, as we have seen.
When I was cruising in the Gulf
Stream, I ventured to enlarge this theory, as the reader may recollect, and suggested that rotation was the normal condition of all extra-tropical winds on the ocean, where there was nothing to obstruct them—of the moderate wind, as well as of the gale.
I had a striking confirmation of this theory in the ‘brave west winds.’
These winds went regularly around the compass, in uniform periods; the periods occupying about three days. We would take them at about N. N. W., and in the course of the ‘period’ they would go entirely around the compass, and come back to the same point; there being an interval of calm of a few hours.
The following diagram will illustrate this rotary motion.
Let Figure 1, on the opposite page, represent a circular wind —the wind gyrating in the direction of the arrows, and the circle travelling at the same time, along the dotted lines from west to east.
If the northern segment of this circular wind passes over the ship, the upper dotted line from A to A2, will represent her position during its passage.
At A, where the ship first takes the wind, she will have it from about northwest; and at A2, where she is about to lose it, she will have it from about south-west.
The ship is supposed to remain stationary, whilst the circle is passing over her. Now, this is precisely the manner in which we found all these winds to haul in the Alabama
. We would have the wind from the north-west to the south-west, hauling gradually from one point to the other, and blowing freshly for the greater part of tree days.
It would then become light, and, in the course of a few hours, go round to the south, to the south-east, to the east, and then settle in the north-west, as before.
Figure 2 represents two of these circular winds—and the reader must recollect that there is a constant series of them— one following the other so closely as to overlap it. Now, if the reader will cast his eye upon the letter C, near the upper
dotted line, in the overlapped space, he will observe why it is, that there is always a short interval of calm before the northwest wind sets in, the second time.
The wind within that space is blowing, or rather should blow, according to the theory, two opposite ways at once—from the N. N. W., and the S. S. E. The
consequence is, necessarily, a calm.
It is thus seen that the theory, that these ‘brave west winds’ are a series of circular winds, harmonizes entirely with the facts observed by us. The lower dotted line is merely intended to show in what direction the wind would haul, if the southern segment, instead of the northern, passed over the ship.
In that case, the ship would take the wind, from about N. N. E., as at B, and lose it at south-east, as at B2. in the region of the ‘brave west winds,’ it would seem that the northern segment always passes over that belt of the ocean.
The received theory of these south polar-winds, is not such as I have assumed.
Former writers have not supposed them to be circular winds at all. They suppose them to pass over the southeast trade-winds, as an upper current, and when they have reached the proper parallel, to descend, become surface-winds, and blow home, as straight winds, to the pole.
But I found a difficulty in reconciling this theory with the periodical veering of the wind entirely around the compass, as above described.
If these were straight winds, blowing contrary to the trades, why should they not blow steadily like the trades?
but if we drop the straight-wind theory, and take up the circular hypothesis, all the phenomena observed by us will be in conformity with the latter.
The periodical hauling of the wind will be accounted for, and if we suppose that the northern half of the circle invariably passes over the ship, in the passageparallels, we shall see how it is that the wind is blowing nearly all the time from the westward.
To account for the fact that the northern half of the circle invariably passes over these parallels, we have only to suppose the circle to be of sufficient diameter to extend to, or near the pole.
here is the figure.
It extends from the parallel of 40°, to the pole; it is therefore fifty degrees, or three thousand miles, in diameter.
Half-way from its northern to its southern edge, would be the 65th parallel.
Along this parallel, represented
by the dotted line, which passes through the centre of the cir. Cle, the vortex, V, or calm spot, would travel.
There should be calms, therefore, about the 65th parallel.
In the southern half of the circle, or that portion of it between the vortex and the pole, easterly winds should prevail.
Navigators between the parallels of 65° and 75°, speak of calms as the normal meteorological condition.
All nature seems frozen to death, the winds included.
Unfortunately, we have no reliable data for the parallels beyond, and do not know, therefore, whether easterly winds are the prevalent winds or not. It is probable, as we approached the pole, that we should find another calm.
The winds, [see the arrows,] as they come hurrying along the circle, from its northern segment, bring with them an impetus toward
the east, derived from the diurnal motion of the earth, on its axis.
As these winds approach the pole, this velocity increases, in consequence of the diminishing diameter of the parallels.
If a particle of air on the equator, having a velocity eastward of fifteen miles per hour—and this is the rate of the revolution of the earth on its axis— should be suddenly transported to a point, distant five miles from the pole, it would have sufficient velocity to carry it entirely around the pole in one hour.
Here we have two forces acting in opposition to each other—the impetus of the wind toward
the east, given to it by the diurnal motion of the earth,
and an impetus from the east, given to it by whatever causes are hurrying it around the circle.
These two forces necessarily neutralize each other, and a calm is the consequence.
It is in this calm region near the poles, that the winds probably ascend, to take their flight back to the equator, in obedience to that beautiful arrangement for watering the earth, which I described some pages back.
There remains but one other fact to be reconciled with our theory.
It has been seen that consecutive circles of wind passed over the Alabama
, in periods of three days each.
Did this time correspond with the known rate of travel of the circles?
Referring again to the last diagram, it will be remembered that the Alabama
was near the northern edge of the circle.
Let A A represent her position at the beginning and end of each wind.
The chord of the segment, represented by the dotted line, is about 1500 miles in length.
The circles travel at the rate of about 20 miles per hour.
Multiply the number of hours—72—in three days, by 20, and we shall have 1440 miles. It is not pretended, of course, that these figures are strictly accurate, but they are sufficiently so to show, at least, that there is no discordance between the fact and the theory.
Soon after leaving the Cape of Good Hope
, the storm-birds began to gather around us in considerable numbers—the Cape pigeon, the albatross, and occasionally the tiny petrel, so abundant in the North Atlantic
These birds seemed to be quite companionable, falling in company with the ship, and travelling with her for miles at a time.
On the occasion of one of the short calms described, we caught an albatross, with hook and line, which measured ten feet across the wings.
The monster bird was very fat, and it was quite a lift to get it inboard.
Though very active on the wing, and rising with great facility from the water, in which it sometimes alights, it lay quite helpless when placed upon the deck.
It did not seem to be much alarmed at the strangeness of its position, but looked at us with the quiet dignity and wisdom of an owl, as though it; would interrogate us as to what we were doing in its dominions.
These birds live in the midst of the great Indian Ocean
, thousands of miles away from any land—only making periodical
visits to some of the desert islands; or, it may be, to the Antarctic Continent
, to incubate and rear their young.
I have described at some length the nature of the great circles of wind which form the normal meteorological condition of the region of ocean through which we were passing.
This normal condition was sometimes interfered with by the passage of cyclones of smaller diameter—a circle within a circle; both circles, however, obeying the same laws.
We took one of these cyclones on the 5th of October.
I do not design to repeat, here, the description of a cyclone, and only refer to that which we now encountered, for the purpose of showing that the Alabama ran a race with it, and was not very badly beaten
. This race is thus described in my journal: Morning dull, cloudy, and cool.
The wind hauled, last night, to north, and is blowing a fresh breeze at noon. Barometer, 30.14.
Thermometer, air 54°, water 60°. Current during the last twentyfour hours, thirty miles east.
The weather continued to thicken in the afternoon, and the wind to increase, with a falling barometer, indicating the approach of a gale.
At nine P. M., the squalls becoming heavy, we furled the top-gallant sails and foresail, close-reefed the topsails, and took the bonnets off the trysails.
Under this reduced sail we continued to scud the ship all night—the barometer still falling, the wind increasing, and a heavy sea getting up. We had entered the north eastern edge of a cyclone.
The next morning the wind was still north by west, having hauled only a single point in twelve hours; showing that we had been running, neck and neck, with the gale.
If the reader will recollect that, in these circular gales, the change of the wind is due to the passage of the circle over the ship, he will have no difficulty in conceiving that, if the ship travels as fast as the circle, and in the same direction, the wind will not change at all. Now, as the wind had changed but a single point in twelve hours, it is evident that the Alabama
had been travelling nearly as fast as the circular gale.
The race continued all the next day—the wind not varying half a point, and the barometer settling by scarcely perceptible degrees.
Toward night, however, the barometer began to settle quite rapidly, and the wind increased, and began to haul
to the westward.
The gale had acquired accelerated speed, and was now evidently passing ahead of us quite rapidly; for by half-past 4 A. M. the wind was at west, having hauled nearly a quadrant in twelve hours. At this point we had the lowest barometer, 29.65.
The centre of the storm was then just abreast of us, bearing about south, and distant perhaps a hundred miles. At five A. M., or in half an hour afterward, the wind shifted suddenly from W. to W. S. W., showing that the vortex had passed us, and that the Alabama
was at last beaten!
The wind being still somewhat fresher than I desired, I hove the ship to, on the port tack, to allow the gale to draw farther ahead of me. After lying to three hours, the barometer continuing to rise, and the wind to moderate, we filled away, and shaking out some of the reefs, continued on our course.
On the 12th of October, we passed the remarkable islets of St. Peter
and St. Paul
, a sort of half-way mile posts between the Cape of Good Hope
and the Strait of Sunda
These islets are the tops of rocky mountains, shooting up from great depths in the sea. They are in the midst of a dreary waste of waters, having no other land within a thousand miles and more, of them.
They are composed of solid granite, without vegetation, and inhabited only by the wild birds of the ocean.
I cannot imagine a more fitting station for a meteorologist.
He would be in the midst of constant tempests, and might study the laws of his science, without interruption from neighboring isle or continent.
There being an indifferent anchorage under the lee of St. Paul
, we scanned the island narrowly with our glasses, as we passed, not knowing but we might find some adventurous Yankee whaler, or seal-catcher, trying out blubber, or knocking a seal on the head.
These islands are frequently sighted by India-bound ships, and it was my intention to cruise a few days in their vicinity, but the bad weather hurried me on.
We took another gale, on the night after leaving them, and had some damage done to our head-rail and one of our quarter-boats.
The scene was a sublime one to look upon.
The seas—those long swells before described—were literally running mountains high, the wind was howling with more than
usual fury, and a dense snow-storm was pelting us from the blackest and most angry-looking of clouds.
I was now in longitude 83° E., and bore away more to the northward.
Although the thermometer had not settled below 50°, we felt the cold quite piercingly—our clothing being constantly saturated with moisture.
On the 14th of October, we had the first tolerably fine day we had experienced for the last two weeks, and we availed ourselves of it, to uncover the hatches and ventilate the ship, getting up from below, and airing the damp bedding and mildewed clothing.
The constant straining of the ship, in the numerous gales she had encountered, had opened the seams in her bends, and all our state-rooms were leaking more or less, keeping our beds and clothing damp.
On the next day, another gale overtook us, in which we lay to ten hours, to permit it, as we had done the gale we ran the race with, to pass ahead of us.
And thus it was, that we ran down our easting, in the region of the ‘brave west winds,’ with every variety of bad weather, of the description of which, the reader must, by this time, be pretty well tired.
On the 17th of October, I was nearly antipodal
with my home in Alabama
By the way, has the reader ever remarked that land is scarcely ever antipodal with land?
Let him take a globe, and he will be struck with the fact, that land and water have been almost invariably arranged opposite to each other.
May not this arrangement have something to do with the currents, and the water-carriers, the winds?
On the morning of the 21st of October, at about five o'clock, we crossed the tropic of Capricorn, on the 100th meridian of east longitude.
We still held on to our west winds, though they had now become light.
We took the tradewind from about S. S. E. almost immediately after crossing the tropic.
We thus had the good fortune, a second time, to cross the tropic without finding a calm-belt; the two counter-winds blowing almost side by side with each other.
We had been twenty-four days and three quarters from the Cape of Good Hope
, and in that time had run, under sail alone— occasionally lying to, in bad weather—4410 miles; the average run, per day, being 178 miles. We had brought the easterly current with us, too, all the way. It had set us twenty
miles to the north-east, on the day we reached the tropic.
In all this lengthened run, we had sighted only two or three sails.
One of these was a steamer, which we overhauled, and boarded, but which proved to be English
For nineteen days we did not see a sail; and still we were on the great highway to India
There must have been numerous travellers on this highway, before and behind us, but each was bowling along at a rapid, and nearly equal pace, before the ‘brave west winds,’ enveloped in his own circle, and shut out from the view of his neighbor by the mantle of black rain-clouds in which he was wrapped.
Our mysterious friends, the Cape-pigeons, disappeared, as we approached the tropics.
We now ran rapidly through the south-east trades, with fine weather, until we reached the 12th parallel of south latitude, when we passed suddenly into the monsoon region.
The monsoons were undergoing a change.
The east monsoon was dying out, and the west monsoon was about to take its place.
The struggle between the outgoing, and the incoming wind would occupy several weeks, and during all this time I might expect sudden shifts and squalls of wind and rain, with densely overcast skies, and much thunder and lightning.
My intention was to make for the Strait of Sunda
, that well-known passage into, and out of the China seas
, between the islands of Java
, cruise off it some days, and then run into the China seas
On the evening of the 26th we spoke an English bark, just out of the Strait
, which informed us that the United States
was cruising in the Strait
, in company with a three-masted schooner, which she had fitted up as a tender, and that she anchored nearly every evening under the island of Krakatoa.
Two days afterward, we boarded a Dutch ship, from Batavia
, which informed us, that a boat from the Wyoming
had boarded her, off the town of Anger
in the Strait
There seemed, therefore, to be little doubt, that if we attempted the Strait
, we should find an enemy barring our passage.
As we drew near the Strait
, we began to fall in with ships in considerable numbers.
On the 31st of October, no less than six were cried from aloft, at the same time, all standing to the south-west, showing that they were just out of the
The wind being light and baffling, we got up steam, and chased and boarded four of them—three English
, and one Dutch
By this time, the others were out of sight—reported, by those we had overhauled, to be neutral—and the night was setting in dark and rainy.
ship, like the last one we had boarded, was from Batavia
, and corroborated the report of the presence of the Wyoming
in these waters.
She had left her at Batavia
, which is a short distance only from the Strait of Sunda
The weather had now become exceedingly oppressive.
Notwithstanding the almost constant rains, the heat was intense.
On the morning of the 6th of November, we boarded an English ship, from Foo Chow for London
, which informed us, that an American ship, called the Winged Racer
, had come out of the Strait
, in company with her. In the afternoon, two ships having been cried from aloft, we got up steam, and chased, hoping that one of them might prove to be the American ship reported.
They were both English
; but whilst we were chasing these two English ships, a third ship hove in sight, farther to windward, to which we gave chase in turn.
This last ship was to be our first prize in East-Indian waters.
A gun brought the welcome stars and stripes to her peak, and upon being boarded, she proved to be the bark Amanda
, of Boston
, from Manilla bound to Queenstown
was a fine, rakish-looking ship, and had a cargo of hemp, and sugar.
She was under charter-party to proceed first to Queenstown
, and thence to the United States
, for a market, if it should be deemed advisable.
On the face of each of the three bills of lading found among her papers, was the following certificate from the British Consul
at Manilla:—‘I hereby certify that Messrs. Ker
& Co., the shippers of the merchandise specified in this bill of lading, are British subjects established in Manilla, and that according to invoices produced, the said merchandise is shipped by order, and for account of Messrs. Holliday
& Co., British subjects, of London
, in Great Britain
As nobody swore to anything, before the Consul
, his certificate was valueless to protect the property, and the ship and cargo were both condemned.
The night set in very dark and squally, whilst we were yet alongside of this
We got on board from her some articles of provisions, and some sails and cordage to replace the wear and tear of the late gales we had passed through, and made a brilliant bonfire of her at about ten P. M. The conflagration lighted up the sea for many miles around, and threw its grim and ominous glare to the very mouth of the Strait
The next day we ran in and anchored under Flat Point
, on the north side of the Strait
, in seventeen fathoms water, about a mile from the coast of Sumatra
My object was to procure some fruits and vegetables for my crew, who had been now a long time on salt diet.