The answer may depend on whether you were doing an installation on top of the old System or a Clean Install. The power interruption probably meant that the System was not expanded, the System Folder blest, &c., &c,. because these happen at the end of the installation. So your new System is not operable, even if it is complete.

If you have a valid Previous System Folder still, because you did a clean installation, you need to get the hard drive mounted, run Disk First Aid and Drive Setup over it and mount it. Diskette 1 should be bootable, and have these utilities on it. If you can mount your HDD, you can either 1) reinstall (and take care to finish) the installation, or 2) rename the botched new System Folder something else (such as Oops), and Previous System Folder (the old one) as System Folder. You will probably have to rebless it by dragging Finder to the desktop, closing the System Folder, and dragging Finder back onto the closed System Folder.

Then start the whole schemozzle again, without the schemozzle. Gaffer tape your AC adapter's DC cable to the floor, wall or ceiling so that it cannot be pulled out. Immobilize the family. Anæsthetize the cat. Whatever it takes. Even buy a battery. Bonne chance.

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