Portable photosynthesis measuring instrument.
Fullsize image: https://s3-us-west-1.amazonaws.com/h...e_fullsize.jpg
https://s3-us-west-1.amazonaws.com/h...ng_machine.jpg
Previously:
https://www.homemadetools.net/forum/...872#post152570
https://www.homemadetools.net/forum/...365#post173297
https://www.homemadetools.net/forum/...743#post159676
https://www.homemadetools.net/forum/...053#post168431
https://www.homemadetools.net/forum/...894#post160120