སྒྱུ་རྩལ
མཛེས་སྡུག་དང་བདེ་ཐང
བཟོ་རིག
རིག་གནས་དང་ལོ་རྒྱུས
དགའ་སྟོན
ཁོར་ཡུག
ཟས་དང་བཏུང་རྫས
ཕྱིར་འཕྲུལ་རིག
ཚན་རིག
རྩེད་འགྲན
རིག་རྩལ
གྱོན་རུང

རྩིས་འཕྲུལ

བིལུ་པིརིན་ཊི ༢༡ ཡོད

བིལུ་པིརིན་ཊི (༢༡)

Quadruplex Telegraphy

Quadruplex Telegraphy

Mark གྱིསFI

གློག་འཕྲུལ

Baudot Code and the Teleprinter

Baudot Code and the Teleprinter

Pixel གྱིསFI

ཨང་གྲངས

The Chappe Semaphore Telegraph

The Chappe Semaphore Telegraph

Astro གྱིསIS

མདོངས་རིག

Hollerith Tabulator

Hollerith Tabulator

Mark གྱིསFI

རྩིས་འཕྲུལ

༡༩
Zero and Place-Value — Build an Abacus and Count Like the World Does

Zero and Place-Value — Build an Abacus and Count Like the World Does

Mark གྱིསFI

བར་དུས

༢༥
The Sand Reckoner — Count the Grains and Tame Huge Numbers

The Sand Reckoner — Count the Grains and Tame Huge Numbers

Mark གྱིསFI

སྔོན་རབས

༢༡
Magic Squares — Arrange Numbers So Every Line Adds the Same

Magic Squares — Arrange Numbers So Every Line Adds the Same

Mark གྱིསFI

སྔོན་རབས

༡༥
The Mercator Map — Peel an Orange and See Why Flat Maps Lie

The Mercator Map — Peel an Orange and See Why Flat Maps Lie

Mark གྱིསFI

Renaissance (1400–1600)

༡༧
Trigonometry — Build a Clinometer and Measure a Tree's Height

Trigonometry — Build a Clinometer and Measure a Tree's Height

Mark གྱིསFI

སྔོན་རབས

༢༡
The Number e — Grow Money and Meet the Constant of Change

The Number e — Grow Money and Meet the Constant of Change

Mark གྱིསFI

Scientific Revolution (1600–1760)

༡༩
The Birth of Probability — Roll the Dice and Find the Odds

The Birth of Probability — Roll the Dice and Find the Odds

Mark གྱིསFI

Scientific Revolution (1600–1760)

༢༣
Descartes' Coordinates — Plot a Treasure Map and Draw with Numbers

Descartes' Coordinates — Plot a Treasure Map and Draw with Numbers

Mark གྱིསFI

Scientific Revolution (1600–1760)

༡༨
Napier's Logarithms — Build a Paper Slide Rule and Multiply by Sliding

Napier's Logarithms — Build a Paper Slide Rule and Multiply by Sliding

Mark གྱིསFI

Scientific Revolution (1600–1760)

༢༣
Newton's Method — Chase a Root Down Tangent Lines You Draw

Newton's Method — Chase a Root Down Tangent Lines You Draw

Mark གྱིསFI

Scientific Revolution (1600–1760)

༢༦
Pascal's Triangle — Build a Pyramid of Numbers by Adding

Pascal's Triangle — Build a Pyramid of Numbers by Adding

Mark གྱིསFI

Scientific Revolution (1600–1760)

༡༦
Al-Khwarizmi's Algebra — Complete the Square with Paper Tiles

Al-Khwarizmi's Algebra — Complete the Square with Paper Tiles

Mark གྱིསFI

བར་དུས

༡༧
Fibonacci Numbers — Count the Spirals on a Pinecone

Fibonacci Numbers — Count the Spirals on a Pinecone

Mark གྱིསFI

བར་དུས

༡༧
Perfect Numbers — Find the Numbers That Equal Their Own Parts

Perfect Numbers — Find the Numbers That Equal Their Own Parts

Mark གྱིསFI

སྔོན་རབས

༡༨
Heron's Square Roots — Fold a Rectangle Toward a Square

Heron's Square Roots — Fold a Rectangle Toward a Square

Mark གྱིསFI

སྔོན་རབས

༢༡
Euclid's Algorithm — Find the Biggest Shared Measure with Paper Strips

Euclid's Algorithm — Find the Biggest Shared Measure with Paper Strips

Mark གྱིསFI

སྔོན་རབས

༡༧