Francis Blake was born in the United States, in Needham (MA) in 1850.
In 1874, Blake married and built a house on his own project in Weston, where he conducted his electrical experiments, which, along with photography, was his primary interest since an early age. Blake was a physicist by profession and 'vocation calling'.
In 1876, when the invention of the telephone was officially announced, Blake became interested in improving the newly created device, which, due to its technical characteristics, clearly needed some improvements.
In 1877, shortly after Thomas Edison created the carbon microphone for telephone sets, an improved device was indeed invented by Francis Blake: his microphone also used carbon granules.
After some time, Alexander Graham Bell invited Blake to join his Company. So a young physicist alongside another American inventor Emile Berliner (who, in 1877, also patented a carbon microphone) continued to work on improving the device.
The microphone, which was improved by Blake and Berliner (by now in the Bell Company for many years) was taken as the industry standard.