In the medieval times, books were very expensive. From the process of making, which was very time consuming and laborious, and further, because of the expensive decorations such are precious stones, gold and jewels with which they were decorated. They were frequently a target of robbers in barbarian campaigns who robbed them, and burned their remains – precious manuscripts, along with the monasteries.
Unfortunately, this is also the reason why many were destroyed, and why we are left with very little of the rich medieval inventory, that is evidenced by catalogs and book lists. But knowledge had to be somehow gathered and transferred to distant parts of the World.
Instead of books – canvases were more accessible and suitable for conveying information. Everything important for a topic would be painted on them, and then they would be rolled up and carried with the rest of the luggage. At the destination, the canvas was unwrapped, hung on the wall and used for work – instead of a book.
I have already painted several canvases, for the needs of the field hospital of the Order of the Guardians of Zagreb. Canvases that show how to treat injuries, how to recognize from the color of urine what the patient is suffering from, or that show the most important plants …
Urine wheel – The doctor would ask the patient for a urine sample, which he would smell, taste and compare with the colors on the canvas, to determine what the person is suffering from