Help needed on a serious of 10 Ordnance Survey of Malta.

the English may not have been soooo popular with the Maltese because there certainly were still many family bonds with Italy. so there was a risk at an Italian invasion for English rule.

 

Malta’s strategic geographical position was of significant importance as a naval base and an interesting attraction for foreign powers seeking to extend their geographical territories and influence- starting from the Phoenicians and ending with the British. Malta was the most heavily bombed place on earth. We are resilient

 

In mean time I uploaded another map. again size approx H 65cm x 87cm . Not too clear especially to full picture of the map

 

The map with the blue lines was probably made with the diazo process, common between 1940s - 1990s.

"...in the 1940s, blueprints were replaced by diazo prints, aka whiteprints or bluelines. [In contrast to cyanotype blueprints, which had white lines on a blue background], diazo prints had blue lines on a white background. They were easier to read and faster to make. The process was simple, the machines were not overly expensive for reprographic companies and didn’t need extensive maintenance. For decades, bluelines were the way to make copies of architectural drawings."
https://www.oncenter.com/blog/article/transitioning-to-the-digital-age/

 

Thank you @ 2manybooks. I am more confused. As the "blueprints" the paper seem much less used "newer" then cyanotype . When in reality they should be older. On the blueprint the ink seem to run . Also why is the writing mirrored, well the whole map is actually mirrored

 

Hi Debora, Are the below photos better?

 

Well not below. you have to go on 1st page

 

The diazo/whiteprint process was used to make copies of maps and architectural drawings, reproducing them in the same size as the original. The original drawing had to be made on a translucent material (something that would let light through). The original was placed in direct contact with the chemically prepared diazo paper, and run through a machine which exposed the sandwich to UV light. The light deactivated the chemicals in the areas where it could penetrate, but the lines of the original drawing blocked light from penetrating in those areas. The diazo copy was then developed - the areas exposed to light becoming white, and the unexposed lines becoming blue.

The image could be reversed/mirrored if the translucent original was placed face down on the diazo paper. They may be unfortunate errors.

If they are diazo whiteprints, they may quickly fade if exposed to light. Such copies were usually kept in closed files or, in your case, rolled up to protect them from light. They were not considered to be permanent documents.
https://en-academic.com/dic.nsf/enwiki/629958

The black-line maps you have shown may have been made with a later photographic reproduction technique. They do not appear to be "blueprints", which would have white lines on a blue paper.

 

Thank you @2manybooks, you really explained that in excellent manner. Yes luckily we kept them rolled up and in a dark cupboard. Only took them out to take some photos. Would the diazo whiteprints be worth anything? Would the later photographic reproduction technique worth anything?

 

I doubt there would be much value, but I don't really know.

 

Thanks appreciate very much your valuable input