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4" F 15 Alvan Clark Refractor

I have the scope, tripod, mount, both Dec and R.A. control rods, crate, eyepieces, terrestrial eyepiece, Herschel Solar diagonal, star diagonal, and lens covers for the main objective and finder.  It has the hard to find number 5 mount. The 4" Clark is 99% original. I did make two brass end pieces and the steel pins to replace the missing ones for the feet of the tripod legs. I have some of the history, but there are a few years which remain obscure. If you know anything about Charles E. Smith who lived in Chicago, IL around 1911,  let me know! Known history of the scope is as follows:

Serial number: # 470
Date of manufacture is 1911
Originally sold to Charles E. Smith from Chicago, IL. 1911
Then an unknown period of history:
It next showed up at antique shop, where Joel Corwin purchased it;
I bought it from him in 1995.

6" F 15 Alvan Clark Refractor

The 6" Clark is not quite as original as the 4". I have the scope, a mount (The John Byrne mount can be seen here), both Dec. and R.A. control rods, tripod, pier, crate, eyepieces, terrestrial eyepiece, Herschel Solar diagonal, star diagonal, lens covers for the main objective and the finder, and much of the history. Known history is as follows:

Serial number: unknown at this time as it is not on the lens.
Date of manufacture is late in 1932. The instrument dealer Rasmussin, from Amsterdam, New York, sold it to George Slack at the Kitchi Gammi Club in Duluth, Minn. in February 1942. He apparently knew the history of the instrument, as he knew when it was made and what came with it when it was originally sold.

Then a period of unknown history until it was owned by Dr. Robert Hardie, from Vanderbilt University. I found out that Dr. Hardie graduated from Chicago, then worked at Yerkes for a while.  Dr. Hardie purchased the Clark from George Slack in 1958. Dr. Giessow bought it from Dr. Hardie in 1964.
I bought it from Mrs. Giessow in September, 1991.

Alvan Clark Heliostat

This was one of only 8 made for the Transit of Venus expedition. (If you haven't seen the website, it is great. Take a peek here. This will open a new window.)



(I added the slow motion control and flat mirror). I have the original crate this came in, and it still has the USNO lettering on it. A complete page on it is here.

History of the 4" & 6" Alvan Clark Refractors


Both my scopes are listed in the new (2nd) version of ALVAN CLARK & SONS, ARTISTS IN OPTICS

One of the things about these, or any old scope, is trying to find out the  history. This is part of the history of my two scopes.

The 4" F15 Alvan Clark & Sons Corpn Telescope circa 1911

My 4" scope is number 470. From the papers, we now know that it was originally sold to C. Smith, Chicago, IL in  1911.

In the (2nd) version of ALVAN CLARK & SONS, ARTISTS IN OPTICS, this scope is listed on page 57 (A.59); page 57 (A.51); page 154 (C.E. Smith); page 196 (C.E. Smith); page 197 (Corp.../Slaton (no. 5 mount)); and page 197 (????..../Corwin)


The 6" F15 Alvan Clark and Sons Telescope circa 1923

In the (2nd) version of ALVAN CLARK & SONS, ARTISTS IN OPTICS, this scope is listed on page 64 (A.95); and page 203 (1930-34 .../Rasmussen/Slack/Hardie/Giessow/Slaton)

My 6" scope had a relatively unknown history for some time. I tried a lot of ways to find out the previous owners -- all with no luck at all. I tried to contact the person who had owned it a couple owners ago, but unfortunately he has passed away. Without going into all the detail, I'll just say that a treasure was found - a folder of papers about the 6". It contained letters from a telescope and instrument dealer in New York named Rasmussen. In these papers, he told a lot of details about the 6" and it's associated equipment, including the mount, tripod, and pier. Following is a copy of one of the letters in the folder: 
(I did minimal editing to correct a few typographical mistakes.)









PH0NE 1341







December 29, 1941

Mr. George Slack
Kitchi Gammi Club
Duluth, Minnesota
Dear Mr. Slack: -

Answering your letter of the 27th, inst. The polar axis mounting can be adjusted to any latitude from 0° to 90°.

There is no sales tax or other federal taxes on the sale of used instruments.

The picture of the pier is like that in manufacturers sheet enclosed, and the mounting is same as shown except the telescope fastens on the saddle with bolts and wing nuts, no body straps are used. The height of the iron pier alone is about 5’ 4" and diameter of base is about 16". Three bolt holes are provided to fasten it onto a cement base.

When we set up a telescope of that size, or any other with iron pier, we make a cement base about 4" larger diameter than the base of the iron pier, and set the galvanized bolts into it, enclosed in galvanized iron pipes with a large cast iron washer between the head of the bolt and the iron pipe. We use pipes quite a bit larger than the bolts, for example, if 5/8" diameter bolts are used we use pipes one inch inside diameter, so to have play enough to center them in the holes of the iron base. We usually use bolts 12" long so to have them about 10" into the cement. We cut the pipes to slip over the bolts 9-1/2" long, which allows ½" for the washers and 2" above the cement. We make a template, a wood board or plank, with holes bored for the bolts to match the holes in the iron base, and fasten the bolts to it, so we can put it onto the top of the form and pour the concrete around it. That assures the bolts in the proper place and holds them rigid while the cement sets. Smoothing of the cement can be done as soon as the form can be removed and the template taken off the bolts. The hole for the cement base, if set in earth, should be not less than 6’ deep. If set on rock, be sure the rock is solid.

The John Byrne, New York, equatorial mounting left on our hands is so much better than the Clark equatorial. It is somewhat heavier; has much better circles with lenses for reading them and the drive clock is geared to that mounting. In case you purchase this telescope it would be better to fit the spare mount equatorial mounting to the iron pier and we keep the Clark mounting to use on some cheaper telescope. This change can be made at a cost of $125. And you would be much better pleased with it.

As stated in the former letter, we can fit the drive clock alone to the Clark mounting at a cost of $75 added to the price of the complete telescope, making it $925 net. Or we can we can fit the better equatorial complete with the drive clock, to the Clark Pier, at a cost of $125 in exchange for the Clark mounting, making the total cost of the telescope $975.

This better equatorial would also be fitted to use on the Clark tripod by simply taking out four bolts and lifting off the mounting. It can be put on the tripod or the iron pier. The drive clock would not be used on the tripod. To disconnect the drive clock simply unscrew one thumbnut holding the drive shaft bracket to the equatorial mounting.

I presume you would want both the tripod and the iron pier with the telescope. In case the tripod is not wanted, we could allow $25 for it.

For your information, the original boxes that the telescope came in when shipped from the factory in late 1932 are here, and would be used. The iron pier has never been uncrated. The original owner used the telescope on the tripod only.