Smithsonian Magazine - Stars in Their Eyes
- The exquisite telescopes crafted by Alvan Clark and his sons helped make the last half of the 19th century a golden age of astronomy.
- http://www.smithsonianmagazine.com/issues/2001/october/refractors.php

Sir Martin Ryle - Nobel Lecture
- Radio telescopes of large resolving power.
- http://nobelprize.org/physics/laureates/1974/ryle-lecture.html

Adler Planetarium - Historical Collections
- Collection of instruments, past exhibitions, history department information.
- http://www.adlerplanetarium.org/history/

Antique Telescopes
- An overview with photographs of many lesser known telescopes typical of their time.
- http://www.antiquetelescopes.org/

The 28-inch Photo-visual Refractor
- Exhibition from the Royal Observatory, Greenwich, that explains the history of this telescope via words and archive photographs.
- http://www.nmm.ac.uk/server.php?request=setTemplate:singlecontent&contentTypeA=conWebDoc&contentId=354&navId=005001004

Virtual Museum of Measuring Engines
- The history of modern astronomical measurement, emphasis on instruments.
- http://www.astro.virginia.edu/~afs5z/engines.html

Important Astronomers, their Instruments and Discoveries
- From the merket to the reflecting telescope in three pages.
- http://seds.lpl.arizona.edu/billa/psc/hist1.html

Churches as Scientific Instruments
- Solar observatories built into 17th and 18th century cathedrals.
- http://cis.alma.unibo.it/NewsLetter/090496Nw/Heilbron.htm

Caltech Astronomy - History
- The telescopes at Mt. Wilson and Palomar.
- http://www.astro.caltech.edu/observatories/palomar/history/

The Astrolabe
- Ancient astronomical computer.
- http://astrolabes.org/astrolab.htm