Today I played with “invisible ink”. After much rummaging about, I finally found a small paintbrush – although it was still quite “fat” at the tip.

Materials:

• lemon juice
• salt solution
• ammonium persulphate solution
• small paintbrush

Lemon juice, onion juice, milk, sugar water, honey solution will all work as invisible inks. As you heat the paper, the message will be revealed by the caramelization of the sugars.

Salty water doesn't work too well. An ammonium persulphate solution works very well, although, I am pretty sure most people don’t have this at home (I use it for etching away copper from printed circuit boards) – and, being corrosive, you don’t want it in contact with the metal nib of a fountain pen (which is why I used a paintbrush).

Writing in invisible ink is tough. The problem is that you can’t see what you are writing. The tendency is to over soak the paper, leaving telltale “water damage” marks. It also take s along time to dry out the page. I was impatient and set the paper to dry atop a hot water radiator. Unfortunately, it seems to have started the revealing of the lemon juice message.

Blank sheet of paper awaiting a message.

Over zealously dried paper with message started to be revealed.

Lemon juice (Invisible ink is cool) was not too great. Of course, the brush also made me write in big sloppy letters.

The salty water (salt) just underneath is barely visible – not really a surprise. Salt is fairly unreactive.

The ammonium persulphate came out very nicely. Of course, it is quite a strong oxidative chemical, so that was no surprise.

One thing for sure, writing in invisible ink with a paintbrush really plays wreaks my handwriting.

Being creative everyday is tough. Of course, some of that difficulty is self-imposed – wanting to do something new everyday and having no clear plan or focus. Today was one of those uncreative days.

On the other hand, doing Thing-A-Day forces me to get out of comfortable routines and patterns; forces me to actually do something instead of just think about it. For me, it is a good exercise.

Today was not a very inspiring day. I went through all sorts of “junk” in the hopes of being inspired, but ... nothing really jumped out at me. In the end, I decided to photograph a vacuum thermocouple and try to make it into a squid or jelly fish type thing by adding more legs using GIMP. In the end, I just grafted it into a picture of a flower I took last Summer.

A vacuum thermocouple. Give it four more legs and an eye and it could pass as some weird octopus. Give it lots of legs and it might pass for a jellyfish.

A poppy from my flower bed in Montreal.

The overlaid images. Not terribly exciting, but I think (in terms of technique) it came out very well.