Here are a few more.
Before 1800, in the States especially, the word 'architect' referred to master carpenters and masons, not a specialized group of people who had not trained in actual hands-on construction.
For more clarification look up the word 'architect' in the OED - the Oxford English Dictionary - which gives origins, sources, and historic uses of words. Its first definition of 'architect' is 'master builder'.
Men who drew and designed buildings, machines, and equipment used compasses. They often had other jobs too - painters, builders, tool makers, teachers, surveyors, erstwhile inventors.They are well-rounded, experienced craftsmen.
Here is James Watt, a famous Scottish inventor with his compass. He vastly improved the efficiency of the steam engine, working on the refinements from about 1765 to 1790. While he refined the parts of the steam engine, he made mathematical instruments and was a land surveyor.
The Britannica has an excellent biography on him.
This sculpture is in the National Museum of Scotland in Edinburgh.
For more pictures and information about James Watt see my blog post:
By the mid-1800's men who drew buildings were beginning to call themselves 'Architects', no longer 'Master Builders'.
Asher Benjamin and others designers are said to have joined together as 'architects' teaching in Boston in the 1840's.*
New York architects created the American Institute of Architects in 1857.
MIT, founded in 1868, was the first school to train architects. The department was, and is, called Course IV. William Ware, mentioned below, was its first Director.
The street directories in Lawrence Massachusetts, 1845-1880, show men who first advertise themselves as carpenters, later listing themselves as builders, and then as architects.
John Haviland called himself an architect. He apprenticed to an architect in England, then sought to become an engineer in Russia, before migrating to the States in 1816. Here he is, with his compass.
For information about the portrait see the blog post listed above for James Watt.
Edward Shaw published his pattern book in 1854. He referred to himself as an architect.
His book discusses design and relationships between parts. It also includes detailed information for carpenters, masons, plasterers.
I wrote about this illustration and the tools shown here in this blog post:
Le Pere Soubise is the legendary founder and saint of the Campagnons Passants Charpentiers de Devoir.
There is more about le Pere Soubise and his compass here: https://www.jgrarchitect.com/2018/02/how-practical-geometry-is-practical.html
An engraving of Giacoma Barozzi da Vignola (1507-1573) with his compass.
Vignola trained under Serlio, then worked in France for Francis I at the same time Serlio was there. He wrote Canon of the Five Orders of Architecture in 1562. It was widely available, reprinted, and translated into many languages. This image is from the edition translated by John Leeke into English in 1669, now available through Dover Publications.
And why did they need compasses? The compass was a tool of layout - for design, for setting proportions. A ruler could then be used to measure those proportions.
*I had the citation about 10 years ago, but cannot find it now. Perhaps it could not be substantiated.
I apologize for the type size changes. If I understood what causes them I would fix them.