Not all SSDs compress.
Another reason for the sparse use of robots is that buildings require a lot more maintenance than just window cleaning. Equipment is needed to lower people to repair facades and broken windows, like the one that rescue workers had to cut through with diamond cutters to rescue the window washers. For many years, being a window cleaner in Manhattan was regarded as one of the most dangerous occupations in the world: by 1932, an average of one in every two hundred window cleaners in New York was killed each year. Now all new union window cleaners now take two hundred and sixteen hours of classroom instruction, three thousand hours of accredited time with an employer and their union makes sure workers follow rigorous safety protocols. In all, there are about 700 scaffolds for window washing on buildings in New York City, says union representative Gerard McEneaney. His members are willing to do the work because it pays well: as much $26.89 an hour plus benefits. Many of the window cleaners are immigrants from South America. "They're fearless guys, fearless workers."
The second effect of World War One took place in the US. Starting in 1917 when the US entered the war, there was a wave of anti-German hysteria that swept the country. In Ohio, Wisconsin and Minnesota there were many, many German speakers. World War One changed all that. "German is criminalized in 23 states. You're not allowed to speak it in public, you're not allowed to use it in the radio, you're not allowed to teach it to a child under the age of 10," says Gordin. The Supreme Court overturned those anti-German laws in 1923, but for years they were the law of the land. What that effectively did, according to Gordin, was decimate foreign language learning in the US resulting in a generation of future scientists who came of age with limited exposure to foreign languages. That was also the moment, according to Gordin, when the American scientific establishment started to take over dominance in the world. "The story of the 20th Century is not so much the rise of English as the serial collapse of German as the up-and-coming language of scientific communication," concludes Gordin.