This is a great old book about the functions of the endocrine glands. To use it, simply open it up and start reading through the chapters. You can read it cover - to - cover or just jump to the sections that interest you. When handling the book, be gentle because it's an old one. Since it's ex - library and has some wear on the cover, try not to add more damage. To keep it in good condition, store it in a dry place away from direct sunlight. This will help prevent further discoloration of the pages. And make sure to close it properly after use to keep the bindings tight.