A DEMONSTRATION OF A CLAUDE GLASS

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Please note: the term "Claude glass" refers to two different tools, one a black mirror, the other a tinted glass lens. This article is about the black mirror.

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Quick Overview

The Claude Mirror, also known as the Lorrain Mirror, is a small, black mirror employed as a drawing aid by artists.

 

Originally intended for viewing sunlit scenery, it alleviated artists’ eyestrain.

 

Named after Claude Lorrain, the French painter who is credited with its invention (though this is disputed), the Claude Glass was popular among 18th-century tourists.

 

Real landscapes reflected in the mirror were evaluated based on their resemblance to paintings by Claude Lorrain.

 

Optically ground, the Claude mirror offers a wider field of view compared to a flat mirror of the same dimensions.

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My photographs were taken in 2001 to illustrate the appearance of an image reflected in a Claude mirror. I had observed online reference sites describing Claude reflections as “sepia,” “neutral,” or “monochrome.” This was an error, as the writers likely had not observed a Claude mirror in use.

 

Drawings created with the assistance of a Claude glass were often monochrome, but the reflections observed in a Claude glass are not.

 

I captured photographs of my Claude glass in use and created an Apple Homepage website to showcase them. One photograph was edited to monochrome to mimic the erroneous notion of a Claude glass reflection.

 

LOCATION

I selected Calton Hill in Edinburgh because the grand, classical monuments there are the type of motif that initially attracted early users.

 

PURPOSE

My photographs demonstrate that a Claudian mirror displays full-colour scenes without glare, enabling the appreciation of qualities such as the rounded shapes of clouds.              

 

Following my correspondence with the editor of an online reference work dedicated to scientific instruments, the editor reviewed my website and expressed his gratitude for my demonstration of the Claude. Consequently, he updated the relevant entry to incorporate the newly acquired information. Regrettably, I am unable to recall the name of the website, nor do I have any knowledge of its continued availability.

 

The “Claude Mirror” is a black, optically ground, convex mirror that is attributed to the French painter Claude Lorrain in the seventeenth century. However, this historical belief is currently disputed by art historians, who assert the absence of any credible evidence to support its existence. The term “optically ground” signifies that when placed in proximity to a flat mirror of the same dimensions, a Claude Mirror exhibits a wider field of vision. It is my understanding that the glass of a genuine Claudian mirror is uniformly dark, rather than simply clear glass with a black backing.

 

Fashionability:

 

The Claude glass gained popularity in the English-speaking world through the works of the poet Thomas Grey and the theorist William Gilpin, who championed the concept of “The Picturesque.” By utilising the Claude glass, artists and travellers were able to observe intensely bright, sunlit scenes for extended periods without experiencing eye strain. This allowed them to discern shapes and details accurately, determine the tonal scale, and utilise their analyses to create drawings, paintings, and verbal descriptions. Consequently, the leisure class could comfortably engage with scenes that captivated their attention.

 

It is plausible that meteorologists might have found the Claude glass to be an invaluable tool in the nascent field of cloud study during that era.

 

Claude glasses fell out of favour around the mid-19th century likely due to the opposition of John Ruskin, who criticised them in “The Elements of Drawing” for distorting tones; he advocated for artists to work directly from nature. During this period, photography was gradually replacing some functions of manual drawing, and Ruskin also cautioned about the potential risks to artists posed by photography: he estimated that the shadows in a photograph were excessively dark by a factor of four. His ideas were embraced by the French Impressionists, who held him in high regard. While I had previously assumed that artists who used “Claude” glasses were professional painters or engravers, some writers contend that they were exclusively employed by amateurs. It remains uncertain whether Claudes have been discovered in the inventories of professional artists, including engravers, from the 17th, 18th, and early 19th centuries.

 

NAMES I refer to the instrument in various ways, partly to match different Internet searches and partly due to my uncertainty regarding its appropriate terminology (capitalisation and synonyms). The exhibition "Garden Futures" at the V&A Dundee displayed my Claude mirror beside a pocket set of  Claude glasses, small tinted lenses in a horn frame. See the photo. 

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INTERPRETATIONS TODAY

Today, there is a school of thought which is interpreting the "Claude" in new ways, e.g. as an 18th century kind of Instagram: "the English were once forward looking, inventive and curious as a nation, and so they came up with their own way to grungify the views they saw on vacation, and (probably) their breakfasts" (from the Web). Instagram is a feature of modern leisure but such interpretations miss the point of what the original users were about. The modern pastime of "filtering" digital images to make them look like products of various obsolete imaging technologies, as seen in "Grunge" graphic design, was not what eighteenth century users of these black mirrors had in mind; there was no pre-existing database of billions of images awaiting "filtering" by Photoshop; making an image was the problem and that could only be done by eye and hand and several visual aids.

 

Claudes were not widely available; during their peak popularity, they were purchased by affluent connoisseurs of landscape art, who occasionally included amateur artists and professional painters and engravers. Following the decline in the popularity of “Claude” mirrors, individuals encountering them might have mistakenly perceived them as oxidised, blackened mirrors or daguerrotypes, leading to their disposal. This was my initial reaction upon encountering one at an uncatalogued auction preview before I realised what is was. 

         

 

PROVENANCE OF MY INSTRUMENT

 

I acquired my instrument at a favourable price during the weekly “Wednesday Hall” sale, which was held at the former Lyon & Turnbull auction house between Thistle Street and Thistle Street Lane, parallel to George Street in Central Edinburgh. The instrument appeared to be unfamiliar to the other attendees, and I was thrilled when it was offered for sale at a low price; I really did jump with surprise when the bidding stopped.

 

SHAPE AND SIZE

I posit that professional topographical artists may have required the larger, somewhat cumbersome, rectilinear examples, while a lady might have only carried a delicate, oval one. My Claude glass exhibits a format reminiscent of engravings depicting towns.

 

The camera I utilised was an entry-level Kodak digital camera. The storage capacity of such a retail consumer camera and the image size permitted on photo-sharing platforms like Homepage were both inferior to what is prevalent today, resulting in my images being somewhat “pixellated.” Following the closure of Homepage, these images have been hosted on other Apple picture servers, but as those have also ceased operation, they are now hosted here.

 

The case is stamped underneath: “Elliott Brothers Opticians 56 Strand London” under a Royal Coat of Arms. According to www.gracesguide.co.uk, “Elliott Brothers; Opticians; 56 Strand; London” traded under this style at this address from 1853 to 1858.

 

Dimensions: 6 1/2 x 5 1/2 x 1 inches.

 

Appearance: Dark greenish leather with a pink silk lining.

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Media Involvement

July 2015:

In July 2015, Spun Gold TV hired the Claude glass for a television production which involved the restoration and completion of the gardens at Belvoir Castle, the seat of the Duchess of Rutland. The series, titled “Titchmarsh on Capability Brown,” aired on Channel Four.

 

Spun Gold expressed their satisfaction with the sequence filmed featuring Alan Titchmarsh using the Claude Glass. They acknowledged the positive impact it had on the series and expressed their gratitude for the opportunity to utilise the product. The sequence was featured in the concluding episode of the three-part series.

 

February 6, 2017:

I am pleased to announce that I have shared the Claude Glass once again, this time with Oxford Film and Television. The production, commissioned by BBC Four, explores the intersection of art and industry.

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April 14, 2025

The Claude glass is on loan for one year to the Victoria and Albert Museum, Dundee, for their exhibition, "GARDEN FUTURES".

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The Claude Glass and Dr Dee

 

Dr John Dee’s Magical Speculum or Scrying Glass was a remarkable artefact in Elizabethan London. Two London museums possess black mirrors believed to be associated with Dr Dee. The Science Museum houses a “Claude glass purported to be John Dee’s scrying mirror, Europe, undated,” while the British Museum holds “Dr Dee’s mirror 1300/1599,” crafted from obsidian rock and of Aztec origin.

 

It is uncertain whether these institutions engage in a competitive rivalry akin to the Louvre and the National Gallery’s dispute over the ownership of “The Virgin of the Rocks.” However, the British Museum’s claim appears more compelling.

 

The Science Museum’s Dee Claude glass is an oval of black glass encased within a wooden box adorned with sharkskin and fastened with conventional brass clasps. The box, reminiscent of those used for scientific instruments of various types, lends credence to the notion that the Science Museum’s Dee mirror could have been acquired from a reputable instrument maker in London, potentially belonging to others. An article similar to this one, observed in London, would not have garnered the same level of notoriety as Dr Dee’s Scrying Glass. Consequently, I posit that this mirror was not Dr Dee’s and that Claude glasses, regardless of their nomenclature, were not prevalent in London during Dr Dee’s era.

 

Throughout history, glass has been employed to replicate objects derived from various stones. For instance, coloured cut crystal glass imitated carved rock crystal, and glass replicated mineral jewels in costume jewellery. Opaque lithyalin glass and malachite glassware are additional examples. It is plausible that the portable black glass mirrors we now refer to as Claude glasses were initially crafted in conscious imitation of Dr Dee’s renowned black stone mirror. Alternatively, it is possible that the entirely oxidised, blackened silvering on old mirrors captivated the imagination of some individuals, leading to the emergence of a fashion for black mirrors.