Describir: Part4: Architecture of Form, variations un tube structure

 ______      ___               _    _    __   _    _    _     ______  
|      \\   / _ \\    ____    | || | || | || | || | || | ||  /_____// 
|  --  //  / //\ \\  |    \\  | || | || | '--' || | || | ||  `____ `  
|  --  \\ |  ___  || | [] ||  | \\_/ || | .--. || | \\_/ ||  /___//   
|______// |_||  |_|| |  __//   \____//  |_|| |_||  \____//   `__ `    
`------`  `-`   `-`  |_|`-`     `---`   `-`  `-`    `---`    /_//     
                     `-`                                     `-`      
 _    _   
| || | || 
| || | || 
| \\_/ || 
 \____//  
  `---`