Cleaning the lens of the 26"

These images, from slides provided by Mihran Miranian, were processed in November 1965.

At this time, the the tin foil placed by the Clarks was replaced with aluminum spacers. Teflon pads were added to the front retaining ring and silicon grease was added to tighten the seal. As you can see in the photos, the telescope was vertical with the lens down. The work table I think was adjustable so it could be raised to the telescope. There were alignment marks on the edge of the two lenses so they could be reassemble correctly. I'm not sure about the cleaning materials, but you can see some of them in the photos. For the process the telescope was vertical and the cleaning was done by dabbing with a lint free cloth with alcohol and distilled water. For removal of the lens, the telescope is vertical.

The bald man in slides 9-12 is George E. Steinacker (Instrument Maker, 1949-72)
The man with the dark tie and glasses in slides 9-12 is Alfred H. (Al) Mikesell, (Astronomer, 1936-70)
The other man with the tie in slides 8 & 10 is Victor M. Blanco (Director A&A, 1965-67)
In slide 12 is Mihran Miranian (Mathematician, 1962-2003)

Black and White Navy photographs and inverse enlarged photocopies from negatives.

In the 7th picture, left to right, are Alfred H (Al) Mikesell (Astronomer, 1936-70), Jonas G Bell (Electronics Tech, 1961-7), Victor M Blanco (Director, A&A, 1965-7) George E Steinacker (Instrument Maker, 1949-1972).
In the 8th picture the other person is Rodney Kip Riddle (Astronomer, 1960-75).
In the 10th picture the other person is Robert R (Robby) Robinson (Laborer/Warehouseman, 1967-97).

Notes from Ted Rafferty regarding Lens Cleaning:

"When I started doing speckle observing with the 26-inch, I did clean the front surface a number of times. Most of the time I just used compressed air and a camel hair brush, but I did clean it with water maybe once every two years or so. I can also remember cleaning the inside surface of the 26-inch lens once or twice by reaching into the "doors" on the side of the tube.
"Cleaning the lens, even very carefully, likely causes scratching, so the lens should only be cleaned when absolutely necessary.
"I did test other cleaning methods, but water (distilled) always worked the best.
"The tricky part about using water is to not let any flow into the cell and get between the elements. I did that once when cleaning the lens for the Six-inch Transit Circle and have to take the lens apart for cleaning.
"Taking a refractor lens apart is very tricky. It is very important not to rotate the two elements in respect to one another. Besides taking the six-inch lens apart, Rich Schmidt and I took the USNO 12-inch lens apart. I also took the lens apart for the Georgetown University 12-inch refractor.
"Taking the lens apart, being able to soak each element, and then drying the elements before putting it back together is surely the best way to avoid scratching the lens.

"Unless there is significant fogging or dirt between the elements, I would suggest not taking the lens apart for cleaning, because the risks of taking the lens apart are so high."