Scientific American magazine has a section called “50, 100 & 150 Years Ago” that features blurbs from the magazine in each of those years. Here is a recent entry for March 1911:
“Concrete for Construction”
“About fifteen years ago serious attempts were made to combine steel and concrete by moulding one into the other in such a way that the resulting product would possess a high resistance not merely to compressive but to bending and tensional stresses. A vast amount of experimental work was done, out of which has sprung our modern reinforced concrete. Not only is concrete found to be available for practically every form of construction which hitherto has been built in brick and stone, but it has now invaded the field which was supposed to be peculiarly reserved for iron and steel.”
If you’ve seen my free video about reinforcing concrete countertops, you know exactly what these compressive, bending (flexural) and tensional stresses are! And you know that your concrete countertop construction methods are based on sound scientific principles. What’s surprising is how recently reinforced concrete was invented, seeing as concrete has been used since Roman times.