|Address||P.O. Box 219 Batavia, IL 60510|
We recommend our Freshwater Pollution Testing Kit, AP5953 and AP5954 (Super-Value Kit) and our Testing Pollution in Tap Water Kit, AP5955 and AP5956 (Super-Value Kit). Both of these kits provide easy tablet-type tests using color comparison charts. These kits can be found in the current Flinn Scientific Catalog/Reference Manual.
We recommend the Acid Rain Survey Kit, AP7054. This kit contains everything you need to collect and monitor the pH of rainwater. Enough materials are provided for over 75 pH determinations.
Refractor telescopes are telescopes that use lenses to gather and focus light. Refractors deliver sharp, high-contrast images with crisp views of the moon, planets and stars. Refractors are known for their rugged simplicity. They are easy to aim, they need little maintenance and lenses rarely need alignment-very popular for beginning students of astronomy.
Reflectors are telescopes that use mirrors. They most commonly use a concave main mirror at the bottom of the tube, which focuses light back up to the top of the tube. There, a small flat mirror deflects the light at right angles to an eyepiece on the side of the tube. Reflectors offer more aperture (objective lens diameter) for the money than refractors, providing enough light to reveal hundreds of deep-sky objects as well as show details of the moon and planets. However, exposed mirrors can collect dust and grime and may need occasional adjustments to keep them properly aligned.