The house numbers 23 and 25 Gwydir Street no longer exist.
In the Spalding directory of 1904, Philip Banyard, a builder, lived in 23 Gwydir St and Zacchaeus Peel lived in 23 Gwydir St.
In the Spalding directory of 1913, Philip Banyard was still at number 23 and David Leach, hosier's assistant, was at number 25.
In the Kelly directory of 1916, Harry Edmund Ambrose, a builder, is at number 23. There is nothing for number 25 (this directory doesn't mention every house).
Albert Biggs emailed me in 2009. He lived at 29 Gwydir Street, where he was born in 1925.
One of your correspondents mentioned the factory that was behind nos 25 to probably no 35. When I first lived there (1925-1950) the factory was Ambroses and they were manufacturing joiners producing all kinds of items for house constuction. In those days the machinery was powered by a single stroke engine powered by town gas and the thump thump thump of the engine was part of daily life. The power was conveyed to the various machines by belt and pulley. Some time at the beginning of the war the factory was taken over by the Simplex company which manufactured items for the dairy trade such as milking machines.
When I first moved to Gwydir Street in 1979, the site was owned by Pye, a major Cambridge employer making radios, televisions and other electrical goods. They had premises all over Cambridge. It's now called the Gwydir Enterprise Centre, with over a dozen different organisations using the units for light industrial use and offices. There is a short road to the site, which is often used for turning vehicles as it is right by the bollards. The area which used to be numbers 23 and 25 Gwydir Street is only part of the site. It extends behind the houses on both sides and juts into the cemetery. See satellite photo from Google maps on the left.