Bouguer, Pierre

Visual colorimetry, probably the oldest analytical method, was last used by the Greeks and Romans. This method found its scientific basis in 1729 when Pierre Bouguer theorised that if a given width of glass absorbs half of the light emitted by a source then double the width will reduce the fight by one quarter its initial value . 

Although the equation that relates absorbance, concentration, and light path bears the names of Beer and Lambert, it is believed that Pierre Bouguer (1698-1758), a French mathematician, first formulated the relationship in 1729. 

Nicolas, S. Gustav Theodor Fechner (1801-1887) et les precurseurs fran9ais de la psychophysique Pierre Bouguer (1729) er Charles Delezenne(1828). Psychologic et histoire 2, 86-130 (2001)... 

Pierre Bouguer (1698-1758) French mathematician, geophysicist, and astronomer Le Havre and Paris, France. 

It is often found, within certain concentration limits, that the intensity of the absorption is proportional to both the concentration, c (mole per liter), and the thickness, / (centimeter), of the sample in the beam that is, the absorbance = tic, where e is defined as the molar extinction coeffident. This relationship is referred to as Beer s law or the Beer Lambert law. The law is named after August Beer (1825-1863), a lecturer in Bonn who studied optics, and Johann H. Lambert (1728-1777), a Swiss mathematician. It has been suggested that Beer s law was initially discovered by the French mathematician Pierre Bouguer (1698-1758). Lambert made reference (with attribution) to it and, much later, Beer extended it to its present form. 

And of course, here we have the advent of Beer s Law, now studied by every introductory chemistry student—a law that lands us squarely in the land of colorimetry. It was actually Pierre Bouguer (1698-1758) who first discovered that the... 

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