http://archive.computerhistory.org/resources/text/Burroughs/Burroughs.OnlineDisk.1962.102646217.pdf
Burroughs.OnlineDisk.1962.102646217.pdf (application/pdf Object)
Burroughs HPT disk was and I believe is the only disk that had a physical head for each track of data. The was no seek time in determining head access to data since the head(s) never physically moved track to track. Rotation time was the only time required to access data from a read/write command. Take a look at the size of each disk platter!
Anyhow, the B200 system mentioned and the HPT subsystem were systems I worked on (fixed) before Burroughs became Unisys.
Page 5 shows a picture with a woman standing. The unit behind her is the central processor. The original CPUs had 4.8 k of character magnetic core memory and a clock speed of 100kc yet these systems were primarily sold to banks who processed all their work on them. Not pictured is a Burroughs B103 check reader. The reader could read 1565 documents (checks) per minute.
I forgot to consider those who are using Commodore machine can't open pdf files. Anyhow, the disk I refer to is approx 3ft in diameter with 4 or 6 disks in a cabinet. Oh well, a picture is worth a thousand words.
Track seek time: 0 ms. :)
They've got some nice computer babes (http://airship.wordpress.com/2007/06/11/models-and-mainframes/) in that brochure, too! Yowrrr! :P