What is a 'Scotch Boiler'? I thought scotch boilers were fire-tube, but I just saw a diagram on here that seems to imply a water-tube design. What gives? - Quora
![Fluids | Free Full-Text | Three Steps Mixed (Fire Tube–Water Tube) Vertical Boiler to Optimize Thermal Performance Fluids | Free Full-Text | Three Steps Mixed (Fire Tube–Water Tube) Vertical Boiler to Optimize Thermal Performance](https://www.mdpi.com/fluids/fluids-06-00093/article_deploy/html/images/fluids-06-00093-g001.png)
Fluids | Free Full-Text | Three Steps Mixed (Fire Tube–Water Tube) Vertical Boiler to Optimize Thermal Performance
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