Technical drawing tools

Physiognotrace

A physiognotrace is an instrument, designed to trace a person's physiognomy to make semi-automated portrait aquatints. Invented in France in 1783–1784, it was popular for some decades. The sitter climbed into a wooden frame (1.75m high x 0.65m wide), sat and turned to the side to pose. A pantograph connected to a pencil produced within a few minutes a "grand trait", a contour line on a piece of paper. With the help of a second scaling-down pantograph, the basic features of the portrait were transferred from the sheet in the form of dotted lines to a copper plate, which had previously been prepared with a ground for etching. One week later, the sitter received an etched plate and twelve little prints. The device but also the aquatint prints are called physionotraces. (Wikipedia).

Physiognotrace
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Introduction to Pharmacology

What are drugs? What do they do? How do they do what they do? These questions are part of the field of pharmacology, and over this series we will learn all about a wide variety of different drugs that have clinical use. This will require a lot of prerequisite knowledge in other fields, so

From playlist Pharmacology

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Research Methods of Biopsychology

With some information regarding the organization of neurons and neural pathways, we are ready to start getting into some deeper topics. But before we do that, it will be useful to get a general sense of precisely how we learn about the things we will be discussing. The brain is complicated

From playlist Biopsychology

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Trigonometry 4 The Area of a Triangle

Various ways of using trigonometry to determine the area of a triangle.

From playlist Trigonometry

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Trigonometry: What Is It?

This video shows how trigonometry is both interesting and useful. Its history, practical uses, place in mathematics and wide use are all covered. If you are wondering why you might want to learn trigonometry, start here!

From playlist Trigonometry

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Find the value of the trigonometric expression using inverse

👉 Learn how to evaluate an expression with the composition of a function and a function inverse. Just like every other mathematical operation, when given a composition of a trigonometric function and an inverse trigonometric function, you first evaluate the one inside the parenthesis. We

From playlist Evaluate a Composition of Inverse Trigonometric Functions

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Introduction to Biopsychology

Let's learn all about the human brain! It's the most complex and fascinating object in the known universe. It's the source of our consciousness, so we wouldn't be much without it. This course will assume prior knowledge from my biochemistry, biology, and anatomy & physiology courses, so ma

From playlist Biopsychology

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Electromagnetic induction and Antigravity!!!

Physics demonstrations (la physique)!!!

From playlist physics

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Trigonometry 6 The Sine of the Sum and the Difference of Two Angles

A description of the sine function of the sum and difference of two angles.

From playlist Trigonometry

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Introduction to Trigonometry: Angles and Radians

Alright, it's time to get into some more challenging math! Trigonometry is a subject that many people find intimidating, but once you understand some new ways to look at angles and some functions that pertain to them, it's really not so bad! First things first, let's make sure we understan

From playlist Trigonometry

Related pages

Pantograph | Polygraph (duplicating device)