Top

Air Conditioning Defined

January 26, 2012 by · Comments Off on Air Conditioning Defined 

Air Conditioning Defined, In 1758, Benjamin Franklin and John Hadley, professor of chemistry at Cambridge University, conducted an experiment to explore the principle of evaporation as a means to rapidly cool an object. Franklin and Hadley confirmed that evaporation of highly volatile liquids such as alcohol and ether could be used to drive down the temperature of an object past the freezing point of water. They conducted their experiment with the bulb of a mercury thermometer as their object and with a bellows used to “quicken” the evaporation; they lowered the temperature of the thermometer bulb to −14 °C (7 °F) while the ambient temperature was 18 °C (64 °F). Franklin noted that soon after they passed the freezing point of water (0 °C (32 °F)) a thin film of ice formed on the surface of the thermometer’s bulb and that the ice mass was about a quarter inch thick when they stopped the experiment upon reaching −14 °C (7 °F). Franklin concluded, “From this experiment, one may see the possibility of freezing a man to death on a warm summer’s day”.

In 1820, British scientist and inventor Michael Faraday discovered that compressing and liquefying ammonia could chill air when the liquefied ammonia was allowed to evaporate. In 1842, Florida physician John Gorrie used compressor technology to create ice, which he used to cool air for his patients in his hospital in Apalachicola, Florida. He hoped eventually to use his ice-making machine to regulate the temperature of buildings. He even envisioned centralized air conditioning that could cool entire cities. Though his prototype leaked and performed irregularly, Gorrie was granted a patent in 1851 for his ice-making machine. His hopes for its success vanished soon afterward when his chief financial backer died; Gorrie did not get the money he needed to develop the machine. According to his biographer Vivian M. Sherlock, he blamed the “Ice King”, Frederic Tudor, for his failure, suspecting that Tudor had launched a smear campaign against his invention. Dr. Gorrie died impoverished in 1855 and the idea of air conditioning faded away for 50 years.

Early commercial applications of air conditioning were manufactured to cool air for industrial processing rather than personal coolness. In 1902 the first modern electrical air conditioning was invented by Willis Carrier in Syracuse, New York. Designed to improve manufacturing process control in a printing plant, his invention controlled not only temperature but also humidity. The low heat and humidity were to help maintain consistent paper dimensions and ink alignment. Later Carrier’s technology was applied to increase productivity in the workplace, and The Carrier Air Conditioning Company of America was formed to meet rising demand. Over time air conditioning came to be used to improve coolness in homes and automobiles. Residential sales expanded dramatically in the 1950s.

In 1906, Stuart W. Cramer of Charlotte, North Carolina, was exploring ways to add moisture to the air in his textile mill. Cramer coined the term “air conditioning”, using it in a patent claim he filed that year as an analogue to “water conditioning”, then a well-known process for making textiles easier to process. He combined moisture with ventilation to “condition” and change the air in the factories, controlling the humidity so necessary in textile plants. Willis Carrier adopted the term and incorporated it into the name of his company. This evaporation of water in air, to provide a cooling effect, is now known as evaporative cooling.

Danny Robbie Hembree Jr. (© NC Department Of Public Safety/AP)

January 26, 2012 by · Comments Off on Danny Robbie Hembree Jr. (© NC Department Of Public Safety/AP) 

Danny Robbie Hembree Jr. (© NC Department Of Public Safety/AP), A death row inmate accused of killing three women and dumping two of them in South Carolina said in a letter to his hometown newspaper that he’ll spend many years getting decent care and enjoying frequent naps before he meets his end.

“Kill me if you can, suckers,” Danny Robbie Hembree Jr. wrote in a letter to The Gaston Gazette .

“Is the public aware that the chances of my lawful murder taking place in the next 20 years if ever are very slim?” Hembree asked. “Is the public aware that I am a gentleman of leisure, watching color TV in the A.C., reading, taking naps at will, eating three well-balanced meals a day?”

The 50-year-old is on death row at Central Prison in Raleigh for suffocating Heather Catterton, 17, in 2009. He’s also accused of the 2009 killing of 30-year-old Randi Dean Saldana, whose burned remains were found near Blacksburg, S.C.

Hembree admitted to taking drugs and having sex with Catterton and Saldana the day they died, but he told jurors he did not kill them or dump their bodies. He is scheduled to go on trial in March for Saldana’s killing.

Hembree also is charged with killing 30-year-old Deborah Ratchford, whose body was found in a Gastonia cemetery in 1992.

“It stirs up their pain. It deepens their grief. It makes it more difficult for them to feel that justice has been done,” said Tom Bennett, of the NC Victim Assistance Network.

He said letters like the one written by Hembree are hard for the victims’ families.

“His criticism, though it’s nasty and horrible for the victims, actually there’s some to truth to it,” said Bennett.

State Representative Paul Stam said the letter is a travesty of justice. He said Hembree is more than likely to die of natural causes than he is of execution.

Bottom