| Regrettably 
              I have not been able to view documentation of any subsequent challenges 
              that were made on this issue. Without further contemporary evidence, what are we left with?
 It 
                might appear that Grover and Baker simply pinched Wilson's described 
                idea, and patented it for themselves later that same year. The 
                problem with this is that Grover and Baker's patent was sealed 
                just seven days after Wilson's. Logically, it seems hard to believe 
                that Grover and Baker could have seen a copy of Wilson's new patent, 
                drawn up their own, and have it submitted and granted all within 
                one week. It's worth remembering that Grover and Baker's patent 
                also contains the other significant modifications to their own 
                machine, which they would have wanted to patent anyway. (Unfortunately, 
                US patents of this period only give the approved date, unlike 
                UK patents, which also show "applied for" dates. I believe 
                very dusty records do still exist in the USA, which contain information 
                on submission dates, etc., but these are not easily accessed.) Could 
                it just be that Grover and Baker, and Wilson conceived the principle 
                of four motion feed at approximately the same time, it was after 
                all a period of very rapid sewing machine development. A second 
                and far more plausible explanation could be that Wilson was in 
                fact marketing a machine which incorporated the new feed some 
                time before his '52 patent was submitted. Messrs. Grover and Baker, 
                after possibly seeing a production machine, had then seized upon 
                this feature as one of great potential and decided to patent it 
                for themselves. |