How can I dump my old iPhoto library into my current library while retaining the original dates, etc? (pics)

[Jerry®]

I - for some unknown stupid reason - have my old iPhoto library from 2 Macs ago just sitting on my Hard drive (I don't know why it wasn't migrated over via migration assistant) - but still in traditional "iphoto" order. Now - I want to dump those photos into my current iphoto library but wanting to retain the original dates, etc. How can I do this?

Here is the path to my current iPhoto library:



and here's my older iPhoto library:




Could I just dump the dated folders from my old library into my current library??

Thanks in advance
Jerry