This is an image of pond water taken from Millikan Pond on Wednesday April 10th in the afternoon. The image was taken at 5 PM on the same day. The sample was obtain from the pond in a plastic vial and then pipetted onto a slide for viewing in the foldscope.

In the image you can see what appear to be cells with a clear outer membrane and darker interior. The image is also somewhat cloudy due to either air bubbles or the lens being dirty.

Some questions I have about the image are: what is the diameter of those cells. In order to know this accurately I would have had to take an image that also included a scale bar in order to have a reference length. It would also be nice to know whether the smudges in the picture are due to the lens being dirty. To know this I would have to take another sample before cleaning the lens to see if the smudges go away. Then, I would clean the lens and take a third sample. If the smudges only went away in the third sample that would show the original smudges in this image are from a dirty lens.

#caltechbi1