Construct this surface which appears like this from various angles: | |

Construct three mutually tangential cylinders of the same size situated like this: |

Arrange three identical mutually tangential cones like this: |

Arrange four identical mutually tangential half-cones like this: |

Arrange eight identical half-cones each tangent to the other three like this: |

Construct the solid bounded by the parabolic cylinder
z = 4 - y and the elliptic paraboloid z = x |