Reference:

Melbourne July 15th 58
Sir We intend to build a shop & house in Stephen St. Melbourne for M Summons No.77 opposite the Wesleyan Church. Thereby inform you respecting the said building about to be commenced. We remain Sir Yours Blewett & Co.

Isaac Summons (1816-1898) was a shopkeeper, based at 172 Stephen Street, Melbourne, now known as Exhibition Street.