A snowball thrower, three exercise machines and a new insecticide were among the seven inventions resulting in patents issued to Utah inventors by the United States Patent Office.

All but the first one were assigned patent numbers greater than 5 million. The issue of patent number 5 million marks an historic occasion as the American patent system enters its third century. Patent number 4 million was issued in the bicentennial year 1976. Another million patents and fifteen years later concludes the celebration of the 200th anniversary of the American patent system.A bacteria modified with genes enabling it to produce ethanol as a fermentation product was given the number 5 million and assigned to the University of Florida.

Roger A. Grosgebauer, Ogden, and C. Max White, Brigham City. A radial pulse rocket motor. Assigned to Thiokol Corporation, Ogden. Filed Nov. 18, 1985. Patent 4,999,997.

K. DeMarr Zimmerman and William J. Robbins Jr., both of Kaysville. A sporting device for forming and throwing snowballs with greater accuracy. Assigned to Sun Products International, Inc., Salt Lake City. Filed Nov. 22, 1989. Patent 5,000,153.

Ralph M. Horton, Murray, and Royce A. Anthon, West Jordan. Low melting point copper-manganese-zinc alloy for rock drill bits. Assigned to Norton Co. Worcester, Mass. Filed Jan. 5, 1990. Patent 5,000,273.

William T. Dalebout and Richard B. Ellis, both of Logan. Cross country ski exerciser. Assigned to Proform Fitness Products Inc., Logan. Filed Feb. 20, 1990. Patent 5,000,442.

William T. Dalebout and Curt G. Bingham, both of Logan. Striding exerciser. Assigned to Weslo, Inc., Logan. Filed Jan. 30, 1989, a continuation of patent 4,850,585. Patent 5,000,443.

William T. Dalebout and Curt G. Bingham, both of Logan. Dual action exercise cycle. Assigned to Proform Products Inc., Logan. Filed Dec. 27, 1988, a continuation of applications June 2, 1988. Patent 5,000,444.

James A. Klocke and Ronald B. Yamasaki, both of Salt Lake City. Azadirachtin derivative insecticides. Assigned to NPI, Salt Lake City. Filed Mar. 4, 1987. Patent 5,001,149.

Barbara Startin, West Jordan. Pair of women's slacks. Filed Nov. 9, 1987. Design patent 315,438.

Copies of patents are available by number for $1.50 from Box 9, Patent and Trademark Office, Washington, D.C. 20231.