Some weeks ago we wrote about noisy fluorescent fixtures, and told you that replacing the ballast would help to solve the problem. Unfortunately, all fluorescent light fixture ballasts hum to some extent, no matter how new or how fine the quality. And, as they get older they hum even louder.

The ballast hums because it is a transformer wire wrapped around a rod. As current passes through the unit, both the wire and the rod vibrate. A new ballast, however, has just come onto the market. It works like a capacitor instead of a transformer. Absolutely no noise. No metal rod and no wire coil.

And silence isn't its only selling point. It also uses less energy. And there's more:

The new "electronic" ballast works with a new bulb that also uses less energy.

Still more:

It gives out more lumens (amount of light) per watt than its noisy ancestor.

More yet:

The new bulbs produce light at a higher Kelvin temperature over 4200 degrees. This means that the color of the light is closer to the color of natural light than the light produced by a fluorescent bulb.

You won't have to change your fixture to convert to the new system. All you'll have to do is change to the new ballast. This could prove to be very cost effective. Let's say you have two four-foot, one-tube fixtures each with its own ballast. You would replace both ballasts with a single new one that works with two four-foot bulbs. One ballast and two bulbs later, conversion is accomplished.

No more noise. Energy savings of about thirteen-percent. More light. And light that looks more like what nature intended.

There doesn't seem to be any reason not to convert to electronic fluorescent.

Our column on levels prompted the following reader suggestions, for which we are grateful:

In your article on making your own level you forgot to mention an important check make sure that no air bubbles exist in the hose. The best way to check for this is to bring the two ends of the tube or hose together, side by side. If the two water surfaces are not even, air bubbles or kinks need to be eliminated. Also, if you are using clear tubing food coloring makes the water within easier to see. Jim N., Camas, Wash.

I really enjoyed your article on levels, but you failed to mention some important information that I think could be valuable to your readers. That is, how to check a level to make sure that it is accurate before you buy it. It really is easy to do.

First, lay the level on a reasonably level surface. A bench or the sales counter it doesn't make any difference whether the surface is perfectly level.

Next, read the level. If it reads perfectly level, that doesn't necessarily mean everything is OK. Do a double-check by holding onto the center of the level and spinning it end for end (180 degrees). If it reads perfectly level in the reverse position, you've got a good one. If not, try the same test on different levels until you get one that gives you the same reading in both positions.

If the counter isn't level, the bubble will appear to one side of center. That's OK, you can still make the test. Say that the bubble has ended up one-eighth of an inch to the right of center. Since this test is performed in the same manner as the first one, the next step is to spin the level as before. If the bubble matches the first measurement one-eighth of an inch to the right of center the level is a good one.