How the abacus, though low tech, became and still remains a very useful tool for those who are blind doing math

The abacus has had a rich history lasting over two thousand years. Ancient merchants needed a way to count things and make calculations. The Asian abaci are the most well known today, both Chinese and Japanese models still exist. The Japanese model has one row of beads with a separation bar and then four more rows of beads below. This model seems to resonate much more with Western minds than the Chinese model. The Chinese model has two rows above the separation bar and then 5 below. I still can’t wrap my mind around those versions. The abacus can still be seen used to calculate prices in some Asian stores including one in Hong Kong as recent as 2013, it is still taught in a few Asian schools, and can also be a useful tool for blind students of any nationality studying math.


Tim Cranmer was born in Kentucky during the depression where he grew up and became a true pioneer in improving the lives of people in the blind community until he died in 2001. Tim studied math and science and found math cumbersome in braille, so he modified the Japanese abacus by inserting a piece of felt under the beads so they wouldn’t slide around as loosely so numbers wouldn’t be disrupted when he and other blind users touched them. This modified Japanese model is called the modified Cranmer abacus, appearing on the market in 1962, and still available today. Tim Cranmer is also credited with inventing the first braille embosser, and also became vast friends with a teenager as they formed the Frankfort Kentucky ham radio club. The teen was Deane Blazie, who ended up working for Tim as his “Saturday boy” over six years until Deane graduated from college. While hanging out and working for and with Tim, Deane learned a lot about technology, and how Tim did things as a blind man. In the end, this all lead to Deane founding Blazie Engineering where he invented the Braille ‘n Speak, the first PDA like device for the blind, before PDAs of that capability even existed for the sighted. I was fortunate to exchange a few emails with Tim shortly before he died, though I didn’t know that then, when I experimented with a multimeter from RadioShack that could be plugged into a computer through the serial port. Tim did a lot for the blind community, was awarded an honorary PHD late in his life, and was still playing with tech when he died.


When I was in elementary school, a talking calculator with the four basic functions cost $500, so in fourth grade one of my teachers taught me how to use an abacus. Several years later Sharp released a basic talking calculator costing $70, affordable to most people including my parents for Christmas when i was in high school. Calculators were not allowed while taking the ACT test so I took in my abacus. The Procter was convinced it was electronic and took 5 minutes trying to find where the batteries were, they finely gave in and let me use it. The abacus is only a place holder for the person as they do all of the calculations, though more in pieces rather than all at once, while the abacus replaces paper, saving the results along the way.

More recently, I found i could do math in binary on an abacus, and used it on Cisco networking exams. No subnet calculators are yet allowed on those either.


With several computers around me as I write this, I still have an abacus on my desk. It’s still more efficient for me to grab it and add up a few numbers, or save a number than to open up a calculator program and leave where I’m currently working.

I know the abacus hasn’t been updated in decades, but it still gets amazing batter–no, still no batteries. When Allison Sheridan, who records the Nosilla podcast, asked her listeners for examples of old technology listeners were still using I just couldn’t resist.


As I said, the person is still doing all the calculations in their head as the abacus keeps track for them, there are methods that can be learned to help with solving specific situations when doing math on the abacus more efficient making the process much faster than it would be if these steps called secrets weren’t memorized. Here is a nice introduction on how the abacus. Is still an under-valued tool,, along with a comprehensive list of resources on how to learn and teach using one.


I am still grateful to my vision teacher in fourth grade, Marina, who taught me the abacus as it has made math easier for me over the rest of my life. Calculators are great, but if one doesn’t understand what the calculator is doing, they may unknowingly accept wrong answers if numbers are entered incorrectly. I wonder how sighted children might benefit if they also learned at least basic abacus skills in early math classes.


Though very low tech, the abacus is still very useful and, at least for me, will never completely be obsolete.

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