The street letter drop mailbox with a hinged door that closed to protect the mail was invented by Philip B. Downing. Downing, an African-American inventor, patented his new device on 27 October 1891.
Marshmallow candy was first made by ancient Egyptians over 3,000 ago. The Egyptians made candy from the root of the marshmallow plant (Althea officinalis), a plant that grows in marshes. Today’s marshmallows do not contain any mallow root – gelatin is substituted for the sweet, sticky root.
Richard G. Drew (1899-1980) invented masking tape and clear adhesive tape (also called cellophane tape or Scotch tape). Drew was an engineer for the 3M company, the Minnesota Mining and Manufacturing.
Drew’s first tape invention was a masking tape made for painters in 1923 – this tape was designed to help painters paint a straight border between two colours). This early masking tape was a wide paper tape with adhesive on only the edges of the tape, not in the middle. Drew made an improved tape called Scotch (TM) Brand Cellulose Tape in 1930. This tape was a clear, all-purpose adhesive tape that was soon adopted
worldwide. The first tape dispenser with a built-in cutting edge was invented in 1932 by John A. Borden, another 3M employee.
The microwave oven was invented as an accidental by-product of war-time (World War 2) radar research using magnetrons (vacuum tubes that produce microwave radiation). In 1946, the engineer Dr Percy LeBaron Spencer, who worked for the Raytheon Corporation, was working on magnetrons. One day at work, he had a candy bar in his pocket, and found that it had melted. He realized that the microwaves he was working with had caused it to melt. After experimenting, he realized that microwaves would cook foods quickly – even faster than conventional ovens that cook with heat. The Raytheon Corporation produced the first commercial microwave oven in 1954; it was called the 1161 Radarange