Okey-dokey. I ran the test at home using two 20W lights and a 4.5 amp battery. She stayed bright about an hour.

This morning was the road test. I didn't use all 40W except when I wanted extra light, such as on descents. 20W seemed bright enough to see the road, and though 40W was better, I kept it in reserve. I had plenty of power for my hour commute. It's recharging in front of my desk, now (my lead-acid battery works best when you recharge fully after every use.) I could probably get by with a single 20W light, but I like the extra power availability.

So, I'm nearing the end of the story. I'm very happy with my low-cost light system. It was extremely easy to put together, mostly because of the battery I bought. I recommend this type of battery because it comes in it's own water-resistant case, comes equipped with a charger and is quickly adaptable to the task. I could probably do it again in less than an hour.

There was an additional cost of about $20 to mount a second 20W light: $12 for the light, $2 for two hose clamps, and $5 for the 3-way switch.

All that remains is to beautify my geek-light. That will come in time. Right now, I'm experimenting with a nipple from a Gerber baby bottle I found in the dollar-store ($1.) This little nipper didn't know why it was made. It thought it was going into a baby's gums, but nooooo, it's going to be promoted to a light switch cover (rain protection.)