Linkage

1. Construct the anti-parallelogram.
   
   
   
   
   
   
   
   
   
   

2. Construct the lemniscate of Bernoulli as the envelope of circles whose center lie on a hyperbola.
   
   

3. Construct the tangent of the lemniscate of Bernoulli.
   
   

4. Construct this linkage to generate an ellipse:
   
   
   
   
   
   

5. Construct Peaucellier's cell:
   
   

6. Construct this linkage:
   
   

7. Make this pattern move.