Dr. Daniel Wallace, Westmoreland County School Board, dazzled students and teachers when he brought a vat of liquid nitrogen to Montross Middle School to demonstrate several principles of science on March 27. He began the presentation by using a block of paraffin wax and aluminum foil to demonstrate how scientists make inferences based on observations. He then proceeded to place several objects into the -321 degrees Fahrenheit nitrogen, such as a daffodil, a balloon animal, a tennis ball, a banana, and pennies. As he removed each item from the liquid nitrogen, Dr. Wallace taught students about how the extreme cold changed the physical properties of the objects. By the end of the presentation, the students had learned a great deal of scientific concepts, and had also thoroughly enjoyed Dr. Wallace’s engaging presentation.