Monday 12 November 2012

Alfred Henry Allen, an extraordinary chemist

My parents have just written a fantastic paper about A. H. Allen, Sheffield's first Public Analyst. Alfred Henry Allen lived from 1846 to 1904, in a time of gas lamps, horse drawn carriages and dubious Victorian era water quality. His chemical investigations and new methods of analysis shone a light on the practices of careless or unscrupulous food and drink manufacturers.

The paper describes lots of his achievements. For example he investigated why the drinking water in some areas of Sheffield contained harmful lead, which was poisoning the population, while other areas had lead-free water (it turns out that the leaded water came from reservoirs which were found to be acidic, and the acid dissolved some of the lead from pipework, so he proposed that the water be treated with lime and limestone to remove the acidity).

Allen investigated the proportions and effects of the different alcohols found in whisky, and even did some testing on himself, drinking a wine glass full of whisky every evening for 3 weeks in order to show that amyl alcohols did no harm. You'll also want to read about his concerns about the "slovenly and ignorant" production of cider, where the cider makers reused manure carts to carry apples.

He didn't just do the science, but also communicated it to a wider audience. He gave public talks and "entertainments", such as Alchemy and the Alchemist, Chemistry of ExplosivesVisible Sound, and Artificial Light. The paper points out that "People in Victorian times had a thirst for entertainment of a scientific and paranormal nature", and I imagine his lectures would have been very popular. Would his talk on Chemistry of Explosives have featured exciting demonstrations that would be impossible today for health and safety reasons? What magic would the lecture on Alchemy have shown?

Allen published over 150 papers and many books on methods of chemical analysis. He wrote 13 volumes of a book called "Commercial Organic Analysis", which needed continual updating as science progressed. He was a founder member of the Society of Public Analysts. He died of diabetes, a disease that had no cure or effective treatment at the time (though Allen had published papers, a book and chemical analysis methods for the determination of sugars in urine, so he would have been well able to measure his condition). During his life, he developed a business of consulting chemists (A.H. Allen & Partners), at which, after many years, my parents worked, and they have now honoured him by documenting his place in history.