Romans

To avoid Neolithic circumstances the Romans need to be studied & skills developed by those who have shelter. I have taken a great deal of trouble learning in the field myself. Engineering, Architecture, imports & their functions, modern location of natural resources, old fashioned refining processes. Those of us who are least use will be first in the pot if food runs low.

Metal mining, smelting, working, soldering etc.
Glass, pottery, bricks, concrete, mosaic
Linen, embroidery, patchwork, fine linen, dyes, jewellery
Water transportation & uses
Wood work, Leather work, embossing, tanning.
Agriculture & transport.

Somebody make us an Encyclopedia omitting irrelevant material. Bind it & laminate the pages. A better standard of library is desirable, hands on.