What is a Reed Organ?
A reed organ can be referenced in many ways. In North America, it is most often referred as a pump organ, cottage organ, parlor organ, cabinet organ or melodeon if it is a suction instrument. If it is a pressure instrument, it is often referenced as a harmonium.
In Europe, South America or generally non-English terms, they are referred as a harmonium, in both pressure or suction styles. Often, they will be referred as "American Organs".
Here are some samples of reed organs and harmoniums: