From Wikipedia, the free encyclopedia

William Aspdin (23 September 1815 — 1864^[1]) was an English cement manufacturer, and a pioneer of the Portland cement industry.

He was born in Leeds. His father, Joseph obtained a patent for "Portland cement" in 1824 and William joined his father's cement manufacturing firm in 1829. His father's product was a fast-setting material usable only in mortars and stuccos. During the next ten years, William evidently noticed that a significantly different product, with much wider applications, could be made by modifying the cement's formulation. By increasing the limestone content in the mixture, and burning it much harder, a slow-setting, high-strength product suitable for use in concrete could be obtained. This product was substantially more expensive to make, in terms of cost of extra limestone, cost of extra fuel, and difficult grinding of the hard clinker. It is unclear whether William actually made this product at his father's plant, but in 1841 he left the firm after major disagreements with his father.

He immediately set up a manufacturing plant at Northfleet, Kent, and was soon making a cement that caused a sensation among users in London. Although this product, referred to today as "modern" Portland cement, was entirely different mineralogically from that of his father, William did not take out a patent, or give it a new name. Apparently, he was aware of the competence of a number of competing manufacturers near to his North Kent plant, and decided that any patent would quickly be infringed by all his rivals. He therefore decided to claim that the product was covered by his father's patent, and clothed the details of his methods in secrecy. Famously, he would emerge from his office when each newly-loaded kiln was ready for firing, and scatter in handfuls of brightly-coloured crystals over the rawmix, in order to give the impression that the special properties of his product were the result of an unidentified "magic ingredient". This strategy kept competition at bay for two years, after which I C Johnson succeeded in matching the product at J B White & Co's nearby Swanscombe plant. See the link for Johnson's own account of this.

He contracted several partnerships in order to finance his operations. He sold out his share of the Northfleet plant in 1852, and set up in Gateshead, County Durham. In 1857, he sold out again, and moved to Germany. From 1860, he set up cement plants at Altona and Lagerdorf, these being the first plants to make modern Portland cement outside the UK^[2]. He died at Itzehoe near Hamburg.

Like his father, William had no chemical knowledge, and his innovations were purely the result of luck. His contribution (although he was unaware of it) was to make the first cement containing alite as an active ingredient. His finances were chaotic, and he was bankrupt at least twice. At each relocation, he was pursued by angry creditors. However, he always took sufficient cash from his businesses to live comfortably, and constructed a substantial concrete mansion - Portland Hall - in Gravesend, Kent.

1. ^ A J Francis, The Cement Industry 1796-1914: a History,David & Charles, 1977, ISBN 0-7153-7386-2
2. ^ G Hägermann, Dokumente zur Entstehungsgeschichte des Portland Zement in Zement-Kalk-Gips, January, 1970

http://www.cement.org/learn/secret_excerpt.asp