On Fri Jul 23 13:50:25 1999,
"Javier Lopez" <[log in to unmask]> wrote:
>Hello friends:
>
>I would like to begin with the study of microshells then my questions are:
>
>Which is the best method to look at them? microscope, binoculars,
>estheresocopic  magnifying glasses ... What do you think?

You need a stereo microscope, also called a dissecting microscope (not a
compound microscope) with a magnification range of about 7x-25x (higher
magnifications cost more money). Stereo microscopes have a high object to
objective distance & they do not reverse images, unlike compound microscopes.
These characteristics make them ideal for examining shells, rocks, and for
dissections. To measure microshells an eye piece with a reticle in it is
needed. Of course, then you will need a stage micrometer to calibrate the
reticle with. The latter is a special slide with a tiny ruler (for example, 1
mm divided to 100) embedded in it. One could also calibrate a reticle using
calipers. All of this costs money. Alternately, for about $50 one could buy a
10x Hastings triplet magnifier. But they have very small object to lens
distances. Avoid all other magnifying lenses for serious work.

What is an "estheresocopic magnifying glass"?

A.