--- title: Encryption In The 1790s | daily.dev description: Thomas Jefferson described a disk-based encryption device in the 1790s, though he likely didn't invent it. The system uses numbered disks with randomly... canonical: https://daily.dev/posts/encryption-in-the-1790s-7spt183tn twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Encryption In The 1790s | daily.dev og:description: Thomas Jefferson described a disk-based encryption device in the 1790s, though he likely didn't invent it. The system uses numbered disks with randomly... og:url: https://daily.dev/posts/encryption-in-the-1790s-7spt183tn og:image: https://api.daily.dev/og/posts/7sPt183Tn.png og:image:alt: Encryption In The 1790s og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Encryption In The 1790s **[Hackaday](https://daily.dev/sources/hackaday)** · 4 min read · 0 upvotes · 0 comments ## Summary Thomas Jefferson described a disk-based encryption device in the 1790s, though he likely didn't invent it. The system uses numbered disks with randomly arranged alphabets on an axle — the sender lines up a plaintext message and sends a different row as ciphertext. The recipient, with matching disks in the same order, finds the only non-gibberish row. Modern analysis rates it as quite secure without knowledge of wheel order. The US Military independently developed a similar device, the M-94 (25 aluminum disks), used from 1922 to 1942, and later the M-138A strip-based variant. The concept also appeared in Etienne Bazeries' 1891 cylinder and was referenced by Charles Babbage in 1854, predating Jefferson's 1790s description. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [Schneier on Security](https://daily.dev/posts/schneier-on-security-btivfoc3r) · Schneier on Security · 0 upvotes · 0 comments - [Alan Turing’s Remarkable, Nearly-Forgotten Voice Encryption Device](https://daily.dev/posts/alan-turing-s-remarkable-nearly-forgotten-voice-encryption-device-cokbuuslj) · Hackaday · 1 upvotes · 0 comments - [Researchers Say New Quantum Encryption Method Can’t Be Copied](https://daily.dev/posts/researchers-say-new-quantum-encryption-method-can-t-be-copied-luzw5ku5m) · The Quantum Insider · 0 upvotes · 0 comments - [Enigma Cipher Device Still Holds Secrets for Cyber Pros](https://daily.dev/posts/enigma-cipher-device-still-holds-secrets-for-cyber-pros-buiazknbz) · Dark Reading · 0 upvotes · 0 comments --- Tags: [#security](https://daily.dev/tags/security), [#cryptography](https://daily.dev/tags/cryptography), [#encryption](https://daily.dev/tags/encryption) [View this post on daily.dev](https://daily.dev/posts/encryption-in-the-1790s-7spt183tn) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Encryption In The 1790s","url":"https://daily.dev/posts/encryption-in-the-1790s-7spt183tn","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/encryption-in-the-1790s-7spt183tn"},"datePublished":"2026-07-23T14:28:14.708Z","dateModified":"2026-07-23T15:48:26.214Z","description":"Thomas Jefferson described a disk-based encryption device in the 1790s, though he likely didn't invent it. The system uses numbered disks with randomly...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/c5d3cd803fd3e479f6fd6d8feb7d86be?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/c5d3cd803fd3e479f6fd6d8feb7d86be?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"Hackaday","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"Hackaday","logo":"https://media.daily.dev/image/upload/s--JhDfhy70--/f_auto,q_auto/v1767541814/logos/hackaday","url":"https://daily.dev/sources/hackaday"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/encryption-in-the-1790s-7spt183tn","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"security,cryptography,encryption","timeRequired":"PT4M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Hackaday","item":"https://daily.dev/sources/hackaday"},{"@type":"ListItem","position":3,"name":"Encryption In The 1790s"}]} ```