Let's discuss vintage (and modern) knots today. First a quick overview of modern knot adhesives. The most popular by far is two-stage epoxy, followed by silicone. Epoxy is a permanent adhesive, and silicone is a semi-permanent adhesive. Both are fairly modern adhesives in the history of brush making. Now that's over with, we'll look at historical adhesives, including ones that are still in use today! The earliest brush adhesive used was boiling pitch or tar. While it was easy to use, it had the disadvantage of being smelly, flammable, and it never really dries out to a solid. Early shave brushes were just wrapped bristles, dipped in pitch, plopped down on a chunk of wood, and then the wood and lower portion of the bristles were covered in leather and wrapped with twine or wire. In America, starting just after the turn of the 20th century, bristles were set using vulcanized rubber in the popular line of shave brushes sold by Rubberset. The company name was the product, a brush with bristles set in rubber. Other American brushes used plaster filled brushes, and their bristles were set in the traditional British manner. Wheat paste. Some of you may be familiar with this glue, which you may have used as children in school, making Papier-mâché covered balloons or pinantas. Simpson's still uses wheat paste adhesive, and the number of vintage Simpson's brushes that are still in use today is a testament to it's effectiveness. I believe that Kent, Morris & Forndran, Culmak, Vulfix and Rooney still use this traditional method of setting knots. Due to the secretive nature of English brush manufacturers, I cannot confirm this. Indeed, I would be unaware of Simpson's use of this adhesive, except for the postings of Mr. Young, a descendent of Andrew Simpson, and a master brush maker himself. Wheat paste is made from wheat flour, bleached/white works best, and water. Sometimes sugar is added to strengthen the glue. A small amount of copper sulfate is also added to act as a bug deterrent and preservative. Best of all, it costs less than $1 per gallon to make. Recipes are easy to find online. Wheat paste is also used to apply street posters, a practice called "wheat pasting," where a poster (what used to be called "broadsides") is quickly affixed to a wall. Nowadays, it is generally only used by guerilla marketers, activists, protestors, and graffiti artists. A skilled wheatpaster can affix a poster in seconds, using a brush and wheat paste concealed in a large fast food drink cup. The poster is usually rolled up, folded over, and concealed in the wheatpaster's sleeve. A quick coat of wheatpaste on the wall, the poster is slapped up, and another quick coat of wheatpaste over the poster affixes it more or less permanently. Sometimes they will slash the poster after it is affixed with a razor multiple times to make it harder to peel the poster off in one piece. If no one removes them, they will remain in place for years. Toulouse Lautrec absinthe posters were often wheatpasted in guerilla marketing campaigns at the turn of the century, and were so popular with collectors, booklets were printed with instructions on how to remove them from walls without damaging the poster. Wheat paste was also used to apply wallpaper. It was the all purpose glue of a previous age. Since it is so cheap to make, why isn't it still used by us? Well, for one thing, it doesn't work on synthetic knots. It needs a rough or porous surface to adhere to. Badger, boar and other natural fibers provide that surface. The slick filaments of modern nylon derived synthetic knots don't offer a good surface. Second, the paste must be used within several days. It doesn't keep. And third, it's time consuming to make. In today's instant gratification world, the thought of spending a tedious half hour stirring paste to make glue is abhorrent to the average McDonald's customer.