Instructables
The Fitzroy Storm Glass is a weather instrument that became popular in the 1860's for predicting the weather.  It is a sealed glass vial that contains chemicals that crystallize in various formations depending on changes in the weather. Admiral Fitzroy, Captain of the HMS Beagle, conducted a study and perfected the formula during the years of 1831 to 1836. The exact origin of the instrument is unknown and believed to have been invented around the 1700's. Because the instrument is somewhat fragile, I wanted to make something that would allow hanging on a wall and safely illuminate for observation. The hanger is made to prevent the storm glass from tipping over. White leds with a variable dimmer using a LM317 are used for illumination. I got the storm glass from Klockit
 
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Step 1: General layout

Picture of General layout
The parts for the wooden hanger is made from 1/2 inch hardwood plywood. Three pieces are used. A back plate, base shelf and a piece midway to stabilize the tube on the base.

Step 2: Base and Shelf

Picture of Base and Shelf
Two pieces are used for the base and shelf. All 1/2 inch hardwood plywood. The base has a portion bored out to hold the base of the storm glass. I used a 2 inch hole saw to bore half-way down then a 1-1/2 inch flat spade bit to take out more area.  A screw driver or chisel can be used to clean out the rest. The top shelf, uses a 1 inch bore saw to make the hole.

Step 4: Back panel holes

Picture of Back panel holes
Four holes need to be drilled on the back plate to mount the base and shelf. Use 1-1/4 flat head screws and pre-drill holes slightly smaller than the screw's diameter to prevent the wood from splitting. Countersink the holes to keep the screws flush on the back. Attach a screw, then carefully square-up the assembly before attaching the second screw. This will allow accurate and square placement of each piece.
graydog1111 year ago
Nice instructable. Have you had the Fitzroy long enough to form an opinion of it? I am interested in getting one if it works reasonably well.
botronics (author)  graydog1111 year ago
If it gets warm enough during the day, most of the crystals will be dissolved and the solution will be supersaturated. If the temperate drops fast enough, such as if a storm was coming in, crystals will fall out a "snow". This is shown in my video. So perhaps it may work to predict a approaching storm. During the summer, when its hot, the crystals should stay well dissolved. I eventually plan to do a long term time lapse video of the glass along with the sky. To predict the weather, I'll trust weather reports. The Fitzroy weather glass, along with a bit of history, still presents an interesting thing to watch.
Samw botronics1 year ago
I was reading that Fitzroy storm glass was also highly affected by humidity. Apparently it was a mandatory piece of equipment in lighthouses in the British Empire for a long period of time.
botronics (author)  Samw1 year ago
I can't see how humidity can effect the instrument since its in a sealed glass tube. More likely the effects of weather that comes along with different levels of humidity is affecting the glass. It is interesting to watch the changes by way of time lapse photography. Right now I have a time lapse session running. The weather has been warm, so not a lot of crystal has occurred.
Thanks, I didn't really expect it to predict the weather, but I think it would be interesting to watch the crystals form and dissolve.
I received a Storm Glass as a gift last Christmas - exactly like the one pictured above. Its kind of a gimmick-y thing. It really only responds to temperature, as you might imagine something inside a sealed glass cylinder might. It does re-crystallize. It was initially clear, now is visibly yellowing. I guess that means its predicting .... I don't know what. My Oregon Scientific internet-based weather display is my go-to device for weather predictions.
botronics (author) 1 year ago
I originally read how to make one in a 1912 copy of The Book of Knowledge, the children's encyclopedia. It was about 45 years ago when I was about 15. Here is a photo of the page with the instructions.
book-of-knowledge.JPG
camforman1 year ago
You may have better luck with the LEDs in series. You will need to guarentee a higher minimum input voltage but you will need 1/3 the current and the LEDs will be guarenteed to share (some have variations in their forward voltage and hog most of the power when in parallel). The voltage may end up being fairly high if white or blue LEDs are used.

If you are having issues with your LEDs not being equal brightness, but can't supply the 16 or 17V required by a series configuration, put a 22 ohm resistor in series with each one to help balance them out.
botronics (author)  camforman1 year ago
Don't need any luck. I was surprised I haven't seen a current hogging problems at all with this circuit. Its true for the best performance, the leds should be in series. I want to use white leds for illumination, so I have to live with the high voltage drop. I didn't want to use anything over 16 volts for the power due to availability. The total current is only 20 milliamps and I don't need to make it less. Most of your multi-led flashlights on the market (and there are millions) just use parallel leds and a series limiting resistor. Using 22 ohm resistors for balance is an excellent idea.
I was reading reviews of this same Fitzroy (same company as the one you ordered) and the chief complaint with them seems to be that once they crystallize initially, they don't continue to change. So, I was wondering, have you experienced such problems with yours?
botronics (author)  builderdude1 year ago
Most people will store their Fitzroy storm glass in the house. Two hundred years ago, we didn't have air conditioning and temperature controlled environments. So in the home, the storm glass doesn't see changes in temperature. I have mine hanging on the wall near a window. During the day, most the crystals will dissolve back. Then overnight and in the morning, the glass is full of growth. The more extreme the temperature change, the more interesting the glass becomes.
billbillt1 year ago
I have to make one of these...Very good!!...
Tomdf1 year ago
How is it that I have never seen one of these in my entire life? Thanks for the introduction, that thing is memorizing!
botronics (author)  Tomdf1 year ago
I remember reading about it 45 years ago when I was a kid. I think it was Scientific American in the Amateur Scientist section. I wanted to make one, but couldn't get all the chemicals. Now the storm glass is pretty common on the internet. The crystals are camphor and the other chemicals effect the solubility, depending on temperature or possibly other factors.
Orngrimm1 year ago
Cool 'ible and MANY thanks for this piece of history and tech behind the glass!
I read the wiki-article and i find those glasses fascinating :)
Thanks.
Probably a silly question but I'm new to reading schematics. On R2 the leg on the right goes back and points to the resistor. How does that connect? Is R2 a potentiometer? It looks like it is in the pic of the control box. Thanks.
botronics (author)  joshvonnieda1 year ago
You connect the center tap of the pot to the ccw leg. Then wire in series with R1. The idea is as you turn the pot clockwise, the resistance get less, but no less than R1.