This is a very old fashioned tile installation method that I learned from my grandfather and then my father in Italy almost 35 years ago when I started them laying tile over wood slabs.

I was attracted by the magnificence of ceramics and since then I wanted to discover all possible tricks to learn.
This method was the only way to go at the time with no putty or tin kit available like now.

A thick slab of clay (5-10 inches) made with a mixture of water, sand and cement mortar is usually laid in 1-6-1 parts or until it forms a crumbly hard clay consistency.
After leveling the entire area by walking on it still wet with special shoes it was time to pour a layer of dry cement mortar and then lay the tiles in one go cuts and field pieces side by side without spacers.

After covering a large portion (nearly 250 square feet) in one go, it was time to beat the shingles with a machine and in some cases where the machine could not reach with a mallet.
This step was fallow, dousing the entire area with a water hose and then spraying a bit of sand, followed by a spray of water again.

The final step was to sweep the wet sand around the grout lines and broom clean the driveway. Final: very primitive but very effective.
No cement slab at the time, no tin set or grout mix to fill the joints. Without wasting time.

Although it is not suggested today to lay tiles too close together within 1/8 inch of a list, this was an effective technique that allowed floors to stay in place for over 20 years.

And it is still in use in Europe today, especially in new multi-level residential construction.