561. Drilling and tapping cast steel (18:58)

Date:
1941
Summary:
Technique of drilling and tapping blind holes in cast steel on a radial drill. A drill jig with loose bushings is used for locating the holes. Setting up the work on the table of the machine, setting the jig on the piece to the layout lines. Calculating the size of the tap drill and the method used when setting the machine to drill a number of holes to the same depth. A wizard drill chuck is used in the drilling operation, and a standard friction chuck for holding the tap. The action of a tap in a hole is shown in animation and the reason why a tap binds in the hole and must be reversed frequently when tapping in tough metals.

562. Double ram verticle surface broaching (29:12)

Date:
1947
Main contributors:
Division of Visual Aids, U.S. Office of Education, Federal Security Agency, Ray-Bell Films, Inc.
Summary:
Shows how to assemble broaching inserts in right- and left-hand toolholders, how to mount and adjust toolholders in the double ram; how to mount and adjust the work fixtures; how to set trip dogs for the ram stroke; how to measure the workpiece after trial broaching; and how to surface-broach on a double ram vertical broaching machine at a production rate.

563. Grinding a V-block (21:16)

Date:
1945
Summary:
Shows how to set up a V-block to grind the ends and the V; how to rough- and finish-grind the ends; how to establish reference points for grinding the V to precision dimensions; and how to check the work for accuracy.

565. The micrometer (15:19)

Date:
1941
Summary:
Shows various types of micrometers; how to use a micrometer, read the barrel and thimble scales, check the accuracy of readings, and take care of the instrument.

566. Grinding a slender shaft with back rest (16:29)

Date:
1947
Main contributors:
Division of Visual Aids, U.S. Office of Education (Producer), Federal Security Agency (Producer), Emerson Yorke Studio (Producer)
Summary:
Shows how to prepare the machine or the job; how to select and set up a back rest; how to adjust the back rest during grinding; how to rough- and finish-grind the long shaft; and how to check and adjust the taper.

567. Grinding and facing a blind hole (16:09)

Date:
1947
Main contributors:
Division of Visual Aids, United States Office of Education (Producer), Federal Security Agency (Producer), Emerson Yorke Studio (Producer)
Summary:
Shows how to mount and dress the wheels on the two-spindle grinder; how to prepare the diaphragm chuck; how to plunge-grind the bore and adjust for taper; and how to grind the shoulder and flange parallel at right angles to the bore.

568. The organization of language (33:48)

Date:
1961
Summary:
The third film in a five-film series, this film illustrates how pre-school children use the forms and arrangements of the words of their language to convey meaning. This is the grammar of the language. This film shows how patterns of organization differ from language to language and are based not so much on logic as on customs and conventions peculiar to each language. A class in German shows how grammatical patterns and their variations are taught by modern methods.

569. DNA structure and replication (29:15)

Date:
1959
Main contributors:
University Films, J. D. Watson, Irwin H. Herskowitz
Summary:
Describes RNA and DNA which are favored as the carriers of genetic information. Presents DNA molecules as shown in the electron microscope and describes the polymeric nature of the DNA molecule and DNA nucleotides. Compares the base content of DNA from various organisms. Describes in detail the three-dimensional organization of DNA as revealed through X-ray diffraction experiments. Pictures a Watson-Crick double helix model of DNA which suggests that DNA may replicate by the two complementary chains separating with each single strand then acting as a template to form its complement. Lecture given by Dr. J. D. Watson.

570. Developmental genetics - II: a lecture by Dr. L. C. Dunn Columbia University (29:41)

Date:
1959
Summary:
Describes the ways in which genes produce phenotypic differences by acting very early in embryonic development. Shows that this action may take place at a distance through chemical messengers (pituitary dwarfism in the house mouse, lethal giant larva in Drosophila), or it may involve tissue induction systems (Brachyury and taillessness in the house mouse). Discusses the development of eye color in Drosophila as a model of how each of the steps in a chain of chemical processes leading to development is under genic control. Lecture given by Dr. L. C. Dunn.