Heavenly city in the moon quotation

Does anyone know the name or number of the ML Berg wrote about the Heavenly City being inside the moon? If it's one of the letters that is available on this site then I'll be able to find a suitable quotation on my own. However, if it's not available here, I'm hoping someone would be able to provide me with a few quotations that summarize this particular belief. For citation purposes I'll need to know the paragraph numbers of the quotations as well as the title, number, and date of publication. Thanks for your help.