and using chilled coils which not only controlled heat but could lower the humidity to as low as 55%. The device was even able to adjust the humidity level to the desired setting creating what would become the framework for the modern air conditioner. By adjusting the air movement and temperature level to the refrigeration coils he was able to determine the size and capacity of the unit to match the need of his customers. While Carrier was not the first to design a system like this his was much more stable, successful and safer than other versions and took air conditioning out of the Dark Ages and into the realm of science." 1902/1906/1908 – Sir James Mackenzie of Scone, Scotland invented an early lie detector or polygraph. MacKenzie's polygraph "could be used to monitor the cardiovascular responses of his patients by taking their pulse and blood pressure. He had developed an early version of his device in the 1890s, but had Sebastian Shaw, a Lancashire watchmaker, improve it further. "This instrument used a clockwork mechanism for the paper-rolling and time-marker movements and it produced ink recordings of physiological functions that were easier to acquire and to interpret. It has been written that the modern polygraph is really a modification of Dr. Mackenzie's clinical ink polygraph." A more modern and effective polygraph machine would be invented by John Larson in 1921. 1902 – Georges Claude invented the neon lamp. He applied an electrical discharge to a sealed tube of neon gas, resulting in a red glow. Claudes started working on neon tubes which could be put to use as ordinary light bulbs. His first public display of a neon lamp took place on December 11, 1910, in Paris. In 1912, Claude's associate began selling neon discharge tubes as advertising signs. They were introduced to U.S. in 1923 when two large neon signs were bought by a Los Angeles Packard car dealership. The glow and arresting red color made neon advertising completely different from the competition. 1902 – Teasmade, a device for making tea automatically, is patented on 7 April 1902 by gunsmith Frank Clarke of Birmingham, England. He called it "An Apparatus Whereby a Cup of Tea or Coffee is Automatically Made" and it was later marketed as "A Clock That Makes Tea!". However, his original machine and all rights to it had been purchased from its actual inventor Albert