Marcus served an apprenticeship in the Maintenance Department of Cammell Laird as a Ship Fitter and Engineers Draughtsman between 11 December 1925 and 29 July 1929, but then was made redundant as a result of the recession. This picture of him was probably taken as an apprentice in his workshop.

He was unable to find employment for four years, but made use of his time to study Radio Engineering upon the encouragement of his brother Blundell. He found work with Lotus Radio between 1931 and 1932 then, from September 1932 to March 1933, with Crane & Sons of Scotland Road in Liverpool, makers of pianos and Harmoniums. After that, he started with The Gramophone Company, (later to become HMV), at Hayes in October 1933, so moved to London and took digs in Central Avenue, Hayes. A colleague called Ernest Walker shared the digs.

Marcus next moved to Plymouth where he found a job as a service engineer in an electrical shop in the main street. He rented a flat at 19 Caprera Terrace and was living there when, on 19 October 1935, he married Edith Lilian Swinnerton.

Unfortunately, soon after his marriage, Marcus lost his job, despite having prevously told his employer that he was to be married and hoped that the job would last. He then went to work for the Singer Company at Barton Hall outside Paignton. He also worked in a Radio shop in Paignton at some time.

Marcus found a job with Pilot Radio in Park Royal, London, and Edie soon joined her husband and they lived in Harlesden. Marc's brother Frank came to lodge with them for a while whilst he was out of work himself. Marc taught him one night how to read an electrical drawing, then got him a job with Pilot Radio. However, Frank lost his nerve and did not come back to work on the second day. When Frank did find work, he moved into a ground floor flat in the same building.

Early in 1937, Marc's friend Ernest Walker got in touch with him to offer a place as the first draughtsman in the new radar research establishment at Bawdsey Manor near Felixstowe. Ernest then lodged with Marc and his wife after they had moved and found a house in Felixstowe. There is an example of a Christmas card that was available for staff.

At the beginning of World War 2, the staff at Bawdsey Manor were moved at short notice for purposes of security. Some went to Perth, but Marcus and others were sent to Leighton Buzzard in an RAF lorry. After a short while, Marcus was transferred to the Royal Aircraft Establishment at Farnborough.

In 1946, he was working in a team at Ambarrow Court in Sandhurst, which was a Victorian House which had been taken over by the Ministry of Air Defence for secret work. The team was engaged on basic research for component monitoring techniques. Later, whilst working on the airfield site of the RAE he was located in building P161 as demonstrated by the address on this envelope. Some of the work he was engaged in was the design of mobile radar units. It is believed that he also was involved with design work on the development of the supersonic liner Concorde.

There are some pictures of Marcus with his colleagues and also an example of a staff Christmas card.

As Marcus lived close to the airfield, he was able to get home for his lunch each day. The family, however, did not like living so close to the sirfield as the planes flew low over the house.

Marcus sought to better himself by looking for alternative jobs, but without success. When he and Edie decided to move to Dorset, he applied for a transfer to the SRDE in Christchurch, but was told that he would have to resign and reapply. However, the matter was resolved when he was offered early retirement due to staff cutbacks.

On 18 February 1972, Marcus was awarded the Imperial Service Medal in recognition of meritoroius services.

Upon his death on 21 November 1973, and after less than two years retirement, a brief obituary appeared in the RAE house magazine.