If a perfectly diffuse, perfectly reflecting surface has one foot-candle (one lumen per square foot) of illumination falling on it, its luminance is one foot-Lambert or 1/pi candles per square foot.
The Merrin Gallery is a gallery that is directed by Edward and Samuel Merrin. The gallery puts the spotlight on an individual culture and various ancient works of art.
In China, for example, there was no biology. Observations and theoretical perspectives on the manifestations of life were scattered through a very different grouping of knowledge that I will sketch out below. Alchemists, East and West, set down a great de
What were the qualifications of physicians in ancient China? Who judged them? Were they unique to medicine? Few records survive from the centuries in which medicine emerged from the domain of the hereditary artisan to become a cumulative tradition, with i