Portland Cement

The manufacturers of Portland Cement are celebrating the 100th anni- versary of their industry.

It was in Leeds, England, 100 years ago, that Joseph Aspdin discovered that a new building material could be produced by mixing pulverized lime and clay in correct proportions and driving out the carbonic acid gas with heat. Aspdin was not a chemist or scientist; and his momentous discovery was made by accidental experimentation. Up until 1872, there was not a Portland cement plant in this country. Today the U. S. industry represents a capital investment of over $300,000,000, employs from 25,000 to 40,000 men, produces annually 25,000,000 tons of cement.

The great day of Portland cement did not set in until cheap structural steel became a commonplace. The reinforced concrete building then came in, as well as concrete roads, concrete canal locks and railroad abutments and many other forms of substitution for solid stonework. Without concrete no less than fabricated steel, the modern skyscraper could never have been built.

Aspdin named his material "Portland cement" because of its resemblance to a type of building stone then commonly quarried on the Isle of Portland. Although the inventor's process has subsequently been improved upon in many ways, the name he gave the product has remained unchanged.