Educational screen & audio-visual guide (c1956-1971])

FILM EVALUATIONS by L. C. Larson and Carolyn Guss Origin of Weather (Carousel Films, Incorporated, 1501 Broadway, New York 36, New York) 26 minutes, 16mm, sound, black and white, no date. $135. Description Through the use of time-lapse and other special photographic techniques, Origin of Weather indicates the present state of knowledge concerning weather and dramatically portrays research by Dr. Joanne Malkus and Dr. Bernard Vonnegut in the area of cloud formation and the creation and effects of storms. The fact that there are more things unknown about the weather than are known is illustrated by dramatic pictures of tornadoes, "runaway" clouds, and hurricanes, causes of which are not yet understood. Other unknowns include the process by which a cloud is formed, what makes rain, what causes lightning, and how the forces in the atmosphere interact to produce high winds or great snow storms. In an effort to find answers to some jf these questions, the audience is taken to the laboratory of Dr. Joanne Malkus. By means of a cup of hot coffee the main ingredients in cloud formation are identified. Much the same atmospheric conditions prevail over tropical oceans as those over the coffee cup. Time-lapse photography is used to show clouds forming, moving and disappearing. Simple line drawings are used to explain the formation of clouds. In order to study the clouds more thoroughly, an airplane is used to take recording instruments of various kinds into the clouds. Most of the clouds, it is pointed out, exist for only about ten minutes, being eroded out of existence by the surrounding cool, dry air. Sometimes, however, a cloud grows so rapidly that the cool air cannot evaporate it. The resulting "run-away" cloud is pictured by means of time-lapse photography. When scientists find out what it is that permits the formation of such giant clouds, Dr. Malkus believes that they will be able to determine what forms and maintains hurricanes. In the North Pacific area the giant "run-avvav" clouds are often formed. By flying between Hawaii and Guam, Dr. Malkus was able to obtain a photographic record of the cloud formations. The motion pictures thus obtained were transformed into a map representation of the cloud formations. The maps clearly show that the clouds tend to line up with the wind. A radar picture of a hurricane is shown and a possible relationship between the arms of the hurricane and the lined-up clouds is proposed. However, if there is a connection between the lining up of the clouds and the formation of hurricanes, it is still not known how the clouds line up nor how they provide the energy to drive the storm. It has long been thought that electricity resulted from rain in a thunderstorm. Dr. Bernard Vonnegut has been doing some experimentation which challenges this accepted view. He suggests that lightning comes first and is a major force in the formation Df rain drops. A simple laboratory demonstration, pictured by slow motion photography, shows the influence of static electricity on the formation of large drops from small drops of water. A small Van de Graaf generator is used by Dr. Vonnegut to explain the formation of electricity in the clouds. He likens the vertical currents of air which carry electrical charges upward to the cloud to the operation of the Van de Graaf generator. To test his theory. Dr. Vonnegut studied the formation of thunderstorms over a mountain range in New Mexico. A photographic record was made of the cloud formations; an airplane was used to fly over and measure the electricity in the clouds; balloons were used to measure the vertical currents of air; and radar was used to determine when raindrops were first formed within the cloud. The information thus recorded was later reduced and compiled in chart form. Electrical activity was shown to precede the formation of rain and seemed to coincide with the growth of vertical currents within the clouds. Although not conclusive, preliminary results tend to support Dr. Vonnegut's theory. Such healthy skepticism and application of experimental science is helping man gain a greater insight into the forces of nature. One day man may control the weather. First, however, he must understand the atmosphere and its activities. Appraisal The preview committee felt that this was an outstanding film for several reasons. It gives a good general view of the problems associated with the understanding and forecasting of weather, and it shows scientists, who are portrayed as real people, at work on a real problem. A healthy skepticism and a willingness to try new things, both of which are essential to scientific progress, likewise are portrayed. Much information concerning weather is presented and the handling of the subject is very interesting. The outstanding feature of the film is the photographic portrayal of weather phenomena. The use of such motion picture techniques as time-lapse and slow motion also contributes much. Teachers on the junior high school through college level will find the film a worthwhile conbibution to the study of weather. On the junior high level the presentation of basic information on weather and the depiction of the scientific method of problem solving should add realism to the understanding of both by a general science class. On the senior high school level the factual information should serve as a good review of knowledge previously acquired and as a springboard to further study. The college student will find challenging the new concept of rain formation, and he will also find interesting the photographic record oi weather phenomena and the methods of collecting data. Originally produced as a television program, this film should find a place for itself among the better educational motion pictures on weather. —Donald Nicholoi Musical Performance: Improvement for Snare Drum (University of Wiscotisin, Madison 6,. Wisconsin) 23 minutes, 16mm, sound; black and white, 1960. $80. Description Through a number of demonstrations, Musical Performance: Improve in Educational Screen and Audiovisual Guide — September, I96G