CO2 manifolds, patents

Since some folks might be swayed by Earle's comments that cheap gang 
airline valves "worked for him", I'll give a little more detail about the 
time I tried this.  I wanted to save a few bucks, so I hooked up

  tank -> regulator -> needle valve -> cheapo gang valves

One problem: the tanks were not all at the same level.  Result: the 
pressure differential between the tanks caused bubbles to only come out 
of ONE tank.  What's worse, the line had a tendency to spontaneously 
become a siphon from the upper tank!

Manifolds are easy to make.  About as easy as you put together the 
regulator->needle valve fitting.  You can buy a little piece of swagelock 
"Tee" costing a couple bucks, and voila!  And as Karen points out, the 
ARO valves are $13 a pop.  Definitely worth it.

> From: Charley Bay <charleyb at hpgrla_gr.hp.com>
> Date: Tue, 3 Oct 95 10:15:46 MDT
> Subject: Re: Yet another plant tank design

[nifty tank idea deleted]
> [embarrassing part]:
> I've heard of people that come up with ideas, use them, and somebody 
> else patents it, and the author can't use it anymore (the courts don't 
> care who the author is).  I really like this design, and have 
> commercial plans.  I don't care who uses it, I just want to be sure 
> *I* can continue to use it (I don't want anybody to patent it and tell 
> me I can't use it anymore).  Is this an issue, or am I just paranoid?  

Why not send a copy of your mail/ascii art directly to the patent office?

Actually, archived postings are amazing things.  Through them, you can 
clearly see, for instance, that Silverstein was the first one to try 
yeast CO2 on the Net, and the Narten was the first one to "refine" it to 
the coke-bottle-and-sugar approach that everyone seems to take credit for 
now. :)

   - Erik

Erik D. Olson					              I'm baaaack!
eriko at wrq_com (was olson at phys_washington.edu)