The article compares different types of progressive hematoxylin stains for coloring tissues like the heart, blood vessels, liver, and spleen. The researchers tested various staining methods to see which one worked best for examining these tissues under a microscope. They found that certain stains were more effective at highlighting specific structures within the tissues, making it easier to study them in detail. This research helps scientists choose the most suitable staining method for studying different organs in the body.