Salt

How does salt float on water when it forms, despite its parts being very fixed and very heavy?

How does it form into small grains, which have a square shape, almost similar to that of a diamond cut in table form, except that the largest of their faces is slightly hollowed?

Firstly, seawater should be retained in some basins to avoid both the continuous agitation of the waves and the influx of fresh water brought by the rains and rivers constantly flowing into the ocean.

Then, hot and dry weather is also needed, so that the action of the sun has enough force to evaporate the parts of the fresh water that are rolled around those of the salt.

The surface of the water is always very smooth and even, as is the case with all other liquids. The reason for this is that its parts move among themselves in the same way and with the same momentum, and the parts of the air that touch it also move among themselves in the same way as each other; but these do not move in the same way or to the same extent as those of the water, and particularly that the subtle matter around the parts of the air moves quite differently from that around the parts of the water.

This causes their surfaces, by rubbing against each other, to become polished in the same way as if they were two hard bodies, except that it happens much more easily and almost instantly, because their parts, not being attached to each other in any way, arrange themselves as required from the first moment.

This is also the reason why the surface of the water is much harder to divide than the inside, as seen by experience in that all small bodies, however heavy their material, such as small steel needles, can float and be supported above as long as the surface is not divided; whereas when it is, they sink to the bottom without stopping.

Following this, it must be considered that when the heat of the air is great enough to form salt, it can not only expel some of the pliant parts from the seawater and cause them to rise as vapor but also lift them with such speed that before they have had time to unfold from around the salt parts, they reach above the surface of this water, where they finish unfolding only after the hole they made in this surface to exit has closed.

As a result, these salt parts remain floating alone on the surface, as you see represented around D. Being laid lengthwise, they are not heavy enough to sink, just like the steel needles I mentioned earlier, and they only cause the surface to bend and curve slightly under them due to their weight, just as those needles do.

Thus, the first salt parts, scattered here and there on this surface, create several small pits or curves; then the subsequent parts, finding themselves on the slopes of these pits, roll and slide towards the bottom, where they join with the first ones.

Wherever they come from, they must lie precisely side by side with these first ones, as you see around E, at least the second ones, and often also the third ones.

Through this, they descend somewhat lower than they could if they remained in any other position, like those seen around F, G, or H. The movement of the heat, which always slightly agitates this surface, helps arrange them in this way.