Henry Dalton was a 19th century microscopist, technically accomplished in slide preparation. He willing shared his techniques and taught others. Dalton had an artistic eye and produced and sold micromosaics, tiny composite images to be viewed through the microscope. Dalton worked with butterfly scales and diatoms to produce intricate pictures and designs. Dalton removed butterfly wings with a needle to create a pallet of shapes and colors. He transferred each scale to the slide with a boar bristle brush to the microscope slide. The scale was coaxed into position and orientation with breath puffed through a tiny tube. The scale could be fixed to the slide with natural oils released by crushing a tiny spot on a scale to the glass. A complex mosaic might contain several hundred to a thousand scales.
The art form is still practiced today by artists who sell slides, some producing custom images. The decline of microscopy as a hobby and the widespread availability of digital images has reduced the demand for micromosaic art. However, the art of microscope slide preparation is widely taught in biology classes and the widespread use of microscopes creates a significant demand for educational microscope slides.