What is a Curta?

[PLS7393]

Watch, learn, and have some fun with Adam Savage!!!

https://www.youtube.com/watch?v=j9uRckJLqLk

Soon to be loaded onto the Mount Diablo Surveyor's Historical Society, various Social Media sites.
Have you found our links? Why are you not a member yet? Collect, Preserve, & Display!

Mt. Diablo turns 175 years old next July, 2026!!!


Keith Nofield,
MDSHS Chariman

[Peter Ehlert]

fun video, thanks.

after all these years I still love my Curta

[dharri]

I used my Curta for a paper weight. Fortunately for me, the HP 35 came along and saved me.

[PLS7393]

A fun post like this, and only a couple comments after four months, so I had to top it?
It appears the profession truly doesn't have much interest in following the footsteps of the original surveyor?
MDSHS (Collect, Preserve, & Display) continues to value the public (and surveyors) on the history of land surveying, even if the newer generation is too busy with their Geo Coordinates.

July 2026, Mt. Diablo Initial Pt. turns 175 years old!!!

Keith Nofield,
MDSHS Chair.
www.mdshs.org

[Peter Ehlert]

Great video, thanks again.
The comments in the video are also entertaining

[Dave Lindell]

I want one!

[desert turtoise]

the round can for calcs my party chief used to grind out by turning that arm on top.Sounded just like an old mechanical coffee grinder. When the electric calculators came out early 70's with the trig functions popping up instantly,he sadly retired his curta.

[DWoolley]

Monroe “Monroematic” Electromechanical Calculator (c. 1940s). I have attached image of mine. I also have a Curta in the case and with the instructions booklet (next image posted separately).

This is a Monroe Monroematic desk calculator, an electromechanical calculating machine produced by the Monroe Calculating Machine Company in the late 1930s–1940s. Driven by an electric motor but using fully mechanical computation, these machines performed automated addition, subtraction, multiplication, and division.

Monroematics were standard tools for land surveyors, engineers, accountants, banks, utilities, and government offices, including widespread use during WWII. They represent the transitional technology between hand-cranked mechanical calculators and later electronic computers. This example appears to date to the WWII or immediate postwar period based on its construction and control layout.

[DWoolley]

My Curta photo attached. It is in brand new condition.

DWoolley

[Peter Ehlert]

Never saw anyone using a Monroe, had one in storage but in 1970 we were electronic in the office.
Sure did use a Curta in the field, very handy.
Still have one on the shelf in the office, with the original handbook and receipt. Think it cost about $65 dollars... not a cheap gadget.

[Jim Frame]

A few years ago I was given a Curta Type 1. Although the can shows signs of having ridden around in a truck toolbox for years, the machine itself is in very good cosmetic shape. Unfortunately, it's bound up -- the crank won't turn, and I don't want to force it. There's a YouTube video of a guy disassembling and lubricating a Curta, so one of these days I'll follow along with the video and see if I can get it working again.

[polaris]

My chainman knew how to use the one we carried around in the truck, in case the electronic calculator batteries died! We had the Curta and log and sine tables in the glove box of our Toyota Landcruiser.

I used the Monroe 354 Surveyor calculator in the office. It was so trick!

Lynn

[Jim Frame]

"One of these days" turned out to be last weekend. I pulled the Curta out again, and removed the bottom plate and outer shell to see if there was any obvious cause of its refusal to turn. Finding nothing but a clean interior, I began firmly but gently working the crank, and it began to move. Continuing that process for about a minute had the gizmo functioning again. A sticker on the inside of the base plate indicates that it was last serviced in 1970, so it'd due for lubrication. There are some good online sources of how to do this, and how *not* to do this. But for now I just buttoned it back up.

And now for the rest of the story: while I had the unit in hand, I decided to remove what I thought was a piece of green tape that was stuck to the body of the calculator. Closer inspection showed that there might have been some writing on the tape (which turned out not to be tape per se, but rather a printed sticker), but it was so badly faded that I wasn't sure. Holding it just right under an illuminated magnifying lens allowed me to start picking out some letters, and after a couple of minutes I could read the name of a San Francisco civil engineer and surveyor. His son is a colleague I've known for about 40 years, though not the surveyor who gave me the Curta.

Thence ensued a battle between the devil on my left shoulder saying, "Why give it back? Bruce will never know you have it!" and the angel on my right shoulder saying, "It was his dad's Curta, you have to return it to him." The fight was brief but decisive, and the angel won. I called Bruce to tell him that I had it, and he said that he had given it to our mutual friend who had given it to me. He said he has a couple more of them, and that I should keep it.

As a final note, I hadn't seen Bruce in a few years, so I did a quick web search to see if I had his current contact information. While looking for that I came across his dad's obit. Ted died in 2021 at age 95, having retired at age 90. He graduated from high school in 1943, joined the army and was a B-24 navigator. He flew 30 missions out of Italy before being shot down and imprisoned by the Luftwaffe. After the war he got his engineering degree at Cal and joined the family business (Ted's father was also a CE and land surveyor). When Korea heated up he was recalled to the service and again flew as a navigator, this time in B-36s.

And that is the rest of the story.

[DWoolley]

And that is the rest of the story.

Good story, especially with the Paul Harvey close. Grew up listening to Paul Harvey news in the morning and The Rest of Story in the afternoon.

Thank you for taking the time to share the story. Gold.

DWoolley

[Scott]

Great story Jim. I also listened to Paul Harvey at lunch for many years.

How about this Friden Automatic Calculator?
Anybody want it?

[SPMPLS]

Although I started in surveying after the Curta era was over (1977), I have always wanted one. About a month ago I saw a Type II in a local antique store. It had the hard shell case but also came with a homemade leather holster. I negotiated a fair price and brought it home. The guy I studied for the exam with in 1986 has one, so I sent him a picture of mine. My phone rang within a minute and he asked where I got it? He then told me that his father had made the leather holster. His dad was a surveyor for Bechtel and worked on all the hydro facilities in the Crystal Basin (Loon Lake, Union Valley reservoir) in the 60's. They lived in Pollock Pines at the time. When I bought the Curta the seller said he got it in Pollock Pines. Bill's dad made holsters for all of the crew chiefs working on that project. Bill has one also, as the Curta he has was his dad's. So, not only did I finally find a Curta, I found one that had a direct tie to the guy I studied for and passed the exam with 40 years ago. Meant to be.

Curta.JPG

[PLS7393]

How about this Friden Automatic Calculator?
Anybody want it?

Hi Scott,
The Mount Diablo Surveyors Historical Society already has a couple Friden's, Monroe's, as well as various models, and other early electronic calculators.
If we did not have your model, it would have been a good home.

Keith Nofield,
MDSHS Chairman