The very first View-Master reels are blue with a gold centre. In about 1940, these were replaced with reels which were blue on the reverse and orange or tan on the front with a blue rim.

A blue reel with buff-coloured rim
In 1941, brown reels replaced the earlier blue and tan ones.

Pale green and pale yellow reels with "hand lettering"
Gradually, the transition was made to white.

A "hand-lettered" white reel
The lettering on these early reels looks like hand lettering although it is printed. The subjects are all topographical, with a heavy bias (as you might expect) towards scenes in the United States of America. These include the Boulder (now called the Hoover) Dam, which was then a new technological marvel, and places like the Grand Canyon.
Most of these reels are hard to find.
The post-war era was a time of huge demand for View-Master and Sawyers responded to this by increasing the number and subject-matter of the reels available.

View-Master Little Red Riding Hood reel and booklet
The fairy-tale reels appeared in 1946. The reel numbers start "FT" and the images use clay figures to tell well-known stories. At first reels were packed singly, but later they were also packed in three-reel sets and in six-reel sets.

View-Master Little Red Riding Hood
Stories included classic fairy tales like Little Red Riding Hood, Christmas tales like The Night Before Christmas and A Christmas Carol.

Religious subjects remained in the View-Master catalogue. This example dates from the 1960s.
In 1947, a special series was issued with actors dressed as authentically as possible portraying well-known stories from the Bible through a series of tableaux. Stories include The Birth of the Savior and The Prodigal Son. These reels have a "CH" prefix.
Other reels produced included the first non-USA topographical reels - some 1947 subjects include London, Stratford-on-Avon, York and Somerset Scenes.

View-Master "Bullfight in Spain"
The range of subjects was extended to cover a variety of events and lifestyles, like Bullfight in Spain (1953), Fire Fighters in Action (1953) and Life with the Cowboys (1951).
More subjects were added throughout the 1950s.
Topographical reels featured more places outside the USA; for example, in 1952 new reels included Mount Fuji, Japan, Festivals of Japan, Tokyo, Maharaja's Festival (Mysore, India), Lahore (Pakistan) and Karachi (Pakistan).
In 1951 Sawyers purchased Tru-Vue which gave them a Disney licence. Disney reels soon joined reels featuring other well-known characters like Bugs Bunny, Tom and Jerry and Woody Woodpecker.
TV characters like Roy Rogers starred on reels in the 1950s, but it was in the 1960s that TV shows started to be featured. Among the well-known shows to have View-Master three-reels sets made are The Man from UNCLE, The Munsters, Lassie, Batman and Bonanza.

View-Master "Coronation of Queen Elizabeth II" packet
Many of the events of the 20th century have been commemorated with a View Master set; Man on the Moon, Coronation of Queen Elizabeth II, Worlds Fair Brussels 1958, Ghent Flower Show 1960 and Expo '70 among them.

View-Master demonstration reel. Note damage to sprocket hole at the bottom of the picture - this is not uncommon
Not all reels were intended for sale - the Demonstration Reels (prefix DR) were given away with the viewer. There are also advertising reels and a series of training reels produced in World War II as training aids for aircraft identification.