What does "corning a place" mean?

Solution 1:

The process of gunpowder manufacture requires the mixing of saltpetre (potassium nitrate, a strong oxidising agent), carbon (charcoal, a coarse substance) and sulphur (a solid). The explosion happens when the mixture is deflagrated to oxidise the carbon and sulphur, suddenly releasing a great deal of energy. This can only happen if the constituents are in intimate contact rather than in coarse block-like contact. For example, three bricks of the constituents laid side by side are unlikely to explode, but if the same quantities of fine grains are mixed (ever so gently!) they are extremely dangerous and vulnerable to the slightest spark. To make gunpowder, the constituents therefore must be mixed and milled to a fine grain size.

Sulphur and charcoal were separately ground small but then had to be mixed with water and saltpetre crystals to make a sludge that could be dried to form a cake. The cake then had to be ground in a corning mill to a fine grain. This process is fraught with risk, which is why gunpowder mills were situated well away from population.

afford = to make available, give forth, or provide naturally or inevitably

"The sun affords warmth to the earth." "a delay that will afford us more time"

Merriam Webster

Corning should therefore be given (afforded) an important place in any account of gunpowder manufacture.

The word corn occurs with similar meaning in corned beef, as you relevantly quote.

I add that the mills were also known as kerning mills. Kerning relates to the spacing between things (as with the granulation of gunpowder) and the word occurs elsewhere, for example:

Kerning typography is the spacing between individual letters or characters.

Adobe

Here is a relevant illustration:

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