The practical lessons thus given in the laboratory are supplemented in an even more tangible manner, because in a way more accessible to the public, in another department of the institution which occupies a contiguous building, and is known as the Museum of Hygiene. This, unlike the other departments of the institute, is open to the general public on certain days of each week, and it offers a variety of exhibits of distinctly novel character and of high educational value. The general character of the exhibits may be inferred from the name, but perhaps the scope is even wider than might be expected. In a word, it may be said that scarcely anything having to do with practical hygiene has been overlooked. Thus one finds here numberless models of dwelling-houses, showing details of lighting, heating, and ventilation; models not merely of individual dwellings, but also of school-buildings, hospitals, asylums, and even prisons. Sometimes the models represent merely ideal buildings, but more generally they reproduce in miniature actual habitations. In the case of the public buildings, the model usually includes not merely the structures themselves but the surroundings--lawns, drives, trees, out-buildings--so that one can get a very good idea of the more important hospitals, asylums, and prisons of Germany by making a tour of the Museum of Hygiene. Regarding the details of structure, one can actually gain a fuller knowledge in many cases than he could obtain by actual visits to the original institutions themselves.