Glass Plate Photographs

In the collection we have over 1000 glass plate photographs. Amongst these are a series of pilgrimage images from Damascus, Syria and Israel. We also have a mix of images featuring Gloucester Cathedral and early 20th-century street scenes, including trams that once ran along routes throughout the city.

Our collection of glass plate photographs includes a wide range of architectural images, featuring church details as well as building exteriors and interiors. These range from country houses to families in front of cottages. With such a wealth of glass plate photography, there are many which require further research and have more stories which are currently untapped.

Before we dive into a special task we’d love your help with, let’s first explore the fascinating world of glass plate photography!

A glass plate photograph of stonework on the exterior/interior of a building. Unknown location. 

What are glass plate photographs? 

Glass plate negatives were used in the 19th century to create clearer photographic images than their paper predecessors. They were made by layering and carefully concocting light-sensitive emulsions, using the glass plate as its base. There were several types of glass plate photographs, which included the use of albumen (the white of an egg!), commonly used in the mid-19th century, a gelatine process, and collodion process. 

The Albumen Process: 

Developed in 1848, a glass plate was expertly covered with a mixture of albumen and light-sensitive chemicals, creating detailed images with 5 to 15 minutes exposure – can you imagine posing for a photo for 15 minutes?! Neither could the Victorians. It soon became apparent that portraiture was not the strong suit of the albumen process. Instead, it was mainly used for architectural and landscape photography. Although used for another couple of decades, it never became widely popular, whether this was due to time, cost and convenience, it cannot be said. It was at this time that the ‘wet’ collodion process was pioneered.  

The Wet Collodion Process: 

The collodion process, introduced around 1851, was considered far easier and more efficient than the albumen process and quickly overtook other forms of photography. To create an image, a glass plate was coated with collodion- a solution of guncotton dissolved in ether - mixed with a small amount of salt. On its own, this mixture couldn’t produce a photograph. However, when silver nitrate was added, it reacted with the salt to form light-sensitive silver chloride. The only drawback to this otherwise ingenious method was that the plate had to remain wet during exposure and development, which led to the term ‘wet collodion process.’”

The inconvenience of the wet collodion process led to the development of the gelatine process. 

The Gelatine Process (‘The Dry Process’): 

From 1871, the gelatin dry process was introduced. Plates could now be stored for weeks before exposure and development. They were no longer wet, which made them more reliable. This prompted further developments in the process, creating a mass-produced version in true industrialisation style, using machines to evenly coat the plates from 1878. These photos were almost instantaneous, perfect for portraiture.

How can you tell your glass plate photograph was made using the gelatine process? They remain dark in front of a dark background. These plates were used until the 1970s!  

A country house with ivy, a vegetable patch and a scarecrow with a top hat! Unknown location and house.

Our glass plate photographs: 

Although it is very fascinating and interesting looking through these glass plates, we are finding that a vast majority of them are not related to Gloucester, or even the surrounding area. In fact, we have an extensive collection of intriguing images of Syria. We do not know who took them, why they were there, or whether they lived in Gloucester at all.

As part of our review of the collection, we are considering the resources we use to look after items which have no Gloucester or Gloucestershire connection, and merely live in storage. We want to be able to share stories about our collection and look after items which are worthwhile for the local community. Many of our glass plates may be more valuable and inspiring to other museums. For example, some beautiful plates of Tintern Abbey could be of greater interest to a local museum. This is just one of hundreds of examples. We’d love your help to learn more about these plates and, where appropriate, find better homes for them in the public domain. We have many images of churches and other buildings that we cannot identify. At present, we don’t have the resources to research them.

We’ve decided to involve the public in identifying where these images were taken, while also sharing our beautiful collection of glass plate negatives. Look out for our ‘Where’s This? Wednesday’ posts on Instagram and help us uncover more about the collection. By working together, we can learn more about Gloucester and Gloucestershire, and even find better homes for some of the slides, ensuring these resources inspire our local community.

References: 

The National Science and Media Museum (2010), ‘A brief guide to photographs on glass’, Accessed from: A brief guide to photographs on glass - National Science and Media Museum blog