|Nils Gustaf Dalén|
Gustaf Dalen invented a light-sensitive valve (the sun valve), the Aga cooker, and the lighting for the Panama Canal, and founded the AGA AB chemical works company, amongst many other things. Not a bad variety for a Nobel Physics Prize winning scientist eh?! A whole menagerie of high-utility inventions from just man.
Nils Gustaf Dalén was born at Stenstorp in Skaraborg, Sweden on November 30, 1869, the son of a farmer. After his preliminary education, he entered a School of Agriculture to study dairy farming but he was later advised by Gustaf de Laval, who recognized his natural gift for mechanics, to seek a technical education. He prepared himself for the Chalmers Institute at Gothenburg and gained admission in 1892. He graduated as an engineer in 1896 and spent a year in Switzerland, studying under Professor Stodola at the Eidgenössisches Polytechnikum.
On his return to Sweden, Dalén carried out some research at Gothenburg and set up as a consulting engineer. He became Technical Chief of the Svenska Karbid- och Acetylen A.B. (Swedish Carbide and Acetylene, Ltd.) in 1901 and he later joined the Gas Accumulator Company where he became Chief Engineer in 1906. In 1909, the company was reorganized as Svenska Aktiebolaget Gasaccumulator (AGA) (Swedish Gas Accumulator Ltd.) with Dalén as Managing Director.
Dalén's inventiveness first showed in his early days on his father's farm when he built a threshing machine powered by an old spinning wheel. He contrived a device to indicate the butterfat content of milk and thereby made his contact with de Laval. On completion of his advanced education, he worked on the construction of a hot-air turbine and related air compressors and pumps. He also invented a pasteurization apparatus and a milking machine.
In 1901, Dalén's company purchased the patent rights of the French invention of dissolved acetylene and he began his work on automatic flashing beacons for lighthouses. His subsequent invention of the sun-valve, which causes a beacon to light automatically at dusk and extinguish itself at dawn, enabled lighthouses to function perfectly and unattended for periods of up to a year. His invention of cylinder filled with a porous mass of asbestos and diatomaceous earth for storage of acetylene reduced considerably the hazards in handling this material and its use in welding became safe. He also invented a mixer for providing a constant and correct balance of gas and air for use in the incandescent mantle and a device for removing broken mantles and replacing them by new ones.
In 1912, whilst testing safety devices on cylinders of acetylene in an outdoor location, and when satisfactory safety precautions had been taken, a sudden explosion seriously injured Dalén and caused the loss of his eyesight. He recovered from his other injuries and overcoming his great incapacity, continued his researches. He was awarded the contract for lighting the Panama Canal and later turned to the field of thermal technics to invent a stove [the Aga cooker - ed], now in universal use, which maintains cooking heat for 24 hours using only eight pounds of coal.
Dalén's writings were few, but he left his mark in a practical way by the provision of light, and therefore safety, for the benefit of travellers by land, sea and air.
Amongst the many distinctions conferred upon Dalén are membership of the Swedish Royal Academy of Sciences, 1913, and the Academy of Science and Engineering, 1919. He was made Honorary Doctor of Lund University in 1918 and received the Morehead Medal of the International Acetylene Association. He took part in debates at the National Society of Economics and served on the Lidingö City Council for almost twenty years.
Dalén married Elma Persson in 1901. They had two sons and two daughters. Their eldest son, Gunnar, qualified as an engineer and followed his father as a Director of AGA; their younger son, Anders, became a Doctor of Medicine; Gustaf's brother Albin, a famous ophthalmologist, was a Professor at the Caroline Institute.
Dalén died on December 9, 1937, in his villa at Lidingö.
One of his inventions, the Aga cooker, is particularly pertinent at this time of year because of course we have Christmas fast approaching which means many needs have to be met including: Christmas dinner (which needs cooking), heating (which is provided for by a gas boiler), and hot water (for that long relaxing bath).
The Aga Rangemaster Group, which Dalen founded, is responsible for the Rayburn Range, which was an improvement on the Aga Cooker because of its high-utility value: It can heat food in pans; It can heat food (or other things) in ovens; It can heat water (e.g. for washing bodies or clothes or dishes, etc); It can heat water for use in radiators around the house; It can be powered by kerosene, diesel, biofuel, gas or electricity. In short, it's a single household appliance that serves many many purposes.
This emphasis on high-utility is very different to the kitchen appliances of the 2010's where single-purpose appliances exist for pretty much every conceivable need. e.g. the toaster for heating bread, an electric kettle for heating ~1 litre of water, an electric steamer for steaming vegetables, an electric deep fryer for chips and doughnuts, the electric grill plate, etc etc. All quite expensive (~£30 per item) and all utterly superfluous if you own a simple, conventional oven and a basic few pots and pans. And let's not forget that you will see many of these appliances advertised down the local shopping centre as Christmas gifts competing for your attention and hard earned cash.
High-utility appliances like the Aga and Rayburn are something to be thankful for because they save us time and effort and cut down on waste, particularly on superfluity. It's something to think about when we are cooking our Christmas dinner in our warm houses. And let's not forget that we have Gustaf Dalen to thank for it.