You are browsing the archive for 2020 March 06.

Avatar of admin

by admin

It Took Surprisingly Long for Doctors to Figure Out the Benefits of Hand Washing

March 6, 2020 in History

By Becky Little

It wasn’t until the mid-19th century that doctors realized going straight from an autopsy to the maternity ward was not a good idea.

One of the best ways to prevent the spread of the flu and other viruses is to wash your hands. Today, this may seem like common sense to many people (even if they don’t all do it properly). Yet it wasn’t until the mid-19th century that some doctors in the United States and Europe began to wash their hands before examining patients—and even then, only in certain cases.

An early proponent of hand washing was Ignaz Semmelweis, a Hungarian doctor who worked at the Vienna General Hospital between 1844 and 1848. The hospital was one of the largest in the world for teaching, and its maternity wing was so big that it was divided into two wards: one for doctors and their students and one for midwives and their students.

Yet there was a stark disparity between these wards.

Between 1840 and 1846, the maternal mortality rate for the midwives’ ward was 36.2 per 1000 births, while the mortality rate for the doctors’ ward was 98.4 per 1000 births, according to a 2013 article in the Journal of the Royal Society of Medicine. Specifically, the doctors’ ward had a higher rate of “childbed fever,” now known as streptococcal infection. Semmelweis started to look for any differences between the wards.

READ MORE: Why the Second Wave of the 1918 Spanish Flu Was So Deadly

One difference was that in the doctors’ division, a priest regularly passed through and rang a bell as a last sacrament to the dying women, explains Dana Tulodziecki, a philosophy professor at Purdue University who has written about Semmelweis in the journal Philosophy of Science. Semmelweis wondered if women were dying because of “the psychological terror of hearing the bell—so even if you’re not actually dying, you just hear the bell, you know it could be your time.” Semmelweis rerouted the priest, but it made no difference.

Then in 1847, the death of Semmelweis’ colleague Jakob Kolletschka led him to a breakthrough. Kolletschka had cut his finger on a scalpel during an autopsy, and developed an infection that killed him. Semmelweis wondered whether a similar type of infection could be happening in the doctors’ maternity ward.

Doctor Ignaz Semmelweis

Semmelweis realized that, unlike the hospital’s midwives, doctors sometimes examined women in the maternity ward …read more


Avatar of admin

by admin

6 Key Inventions by Thomas Edison

March 6, 2020 in History

By Patrick J. Kiger

Edison’s genius was improving on others’ technologies and making them more practical for the general public.

Thomas Edison applied for his first patent in 1868, when he was just 21 years old. The famous inventor’s first brainchild was for a device that recorded legislative votes. That was just the start of a career in which he would obtain 1,093 U.S. patents, in addition to another 500 to 600 applications that he either didn’t finish or were rejected. But Edison’s greatest invention may have been developing a new process for coming up with inventions.

“When Edison raised enormous capital, built a laboratory in Menlo Park, N.J., and hired a staff of several dozen, each with distinct talents, he pioneered what became the modern corporate research and development process,” explains Ernest Freeberg, a historian at the University of Tennessee, Knoxville and author of The Age of Edison: Electric Light and the Invention of Modern America.

“He considered it an invention factory, one that would produce surprising new products at a regular rate.”

In many cases, Edison’s genius was taking a new technology that someone else had pioneered and developing a superior way of doing the same thing. “An invention not only has to work fairly well, but it has to be something that the market wants and can afford to buy. Edison understood that as well as anyone in his day,” says Freeberg.

Below are some of Edison’s most significant inventions.

Automatic Telegraph

Thomas Edison pictured operating a telegraph machine.

While Samuel Morse’s invention of the telegraph in the 1830s and 1840s made it possible for the first time to communicate over long distances, the device had its drawbacks. An operator had to listen to incoming dots and dashes in Morse code, which slowed messages to a speed of 25 to 40 words per minute. A British system for automatically printing code in ink on paper only achieved 120 words tops.

Between 1870 and 1874, Edison developed a vastly superior system, in which a telegraph receiver utilized a metal stylus to mark chemically-treated paper, which then could be run through a typewriter-like device. It was capable of recording up to 1,000 words a minute, which made it possible to send long messages quickly.

Carbon Telephone Transmitter

Cross-section of Edison’s lamp-black button telephone transmitter.

It was Alexander Graham Bell who patented the telephone in 1876. But Edison, …read more