,---------,
|         |
|         |
|         |
|         |
 \       /
  \     /    
   '---'
  sm heater 

,-------------,
|             |
|             |
|             |
|             |
|             |
|             |
|             |
|             |
|             |
|             |
|             |
 \           /
  '\       /'
    '-----'
   big heater


by Mara Kaminowitz