- 
                
                
                    
                        1688929
                    
                                            
                                - 
                                    Patent number 1,688,929
                                
 
                                - 
                                    Issue date Oct 23, 1928
                                
 
                        
                                                                
                                - 
                                        
                                    F28 - HEAT EXCHANGE IN GENERAL
                                 
                        
                 
             
            - 
                
                
                    
                        1542905
                    
                                            
                                - 
                                    Patent number 1,542,905
                                
 
                                - 
                                    Issue date Jun 23, 1925
                                
 
                        
                                                                
                                - 
                                        
                                    F28 - HEAT EXCHANGE IN GENERAL
                                 
                        
                 
             
            - 
                
                
                    
                        1381649
                    
                                            
                                - 
                                    Patent number 1,381,649
                                
 
                                - 
                                    Issue date Jun 14, 1921
                                
 
                        
                                                                
                                - 
                                        
                                    F28 - HEAT EXCHANGE IN GENERAL
                                 
                        
                 
             
            - 
                
                
                    
                        1332092
                    
                                            
                                - 
                                    Patent number 1,332,092
                                
 
                                - 
                                    Issue date Feb 24, 1920
                                
 
                        
                                                                
                                - 
                                        
                                    F28 - HEAT EXCHANGE IN GENERAL
                                 
                        
                 
             
            - 
                
                
                    
                        855374
                    
                                            
                                - 
                                    Patent number 855,374
                                
 
                                - 
                                    Issue date May 28, 1907
                                
 
                        
                                                                
                                - 
                                        
                                    F28 - HEAT EXCHANGE IN GENERAL