Cyanometer Postcard
A cyanometer is a tool that lets you grade the blueness of your sky, invented in 1789 by Horace Bénédict de Saussure.
This genius modern version is combined with a postcard! Simply hold up to the sky, look through the hole and then on the back write the time & shade number. Pop in the post to a friend. 148x105mmÂ
Simple brilliance by Macarena Ruiz-Tagle.
Original: $6.78
-65%$6.78
$2.37Product Information
Product Information
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Description
A cyanometer is a tool that lets you grade the blueness of your sky, invented in 1789 by Horace Bénédict de Saussure.
This genius modern version is combined with a postcard! Simply hold up to the sky, look through the hole and then on the back write the time & shade number. Pop in the post to a friend. 148x105mmÂ
Simple brilliance by Macarena Ruiz-Tagle.
