does "sensitive plate" refers to "Photographic plate" or not?

The author is of opinion that the true explanation will be found by coupling all these happenings with the recent investigations of Dr. Crawford upon the means by which physical phenomena are produced. He showed very clearly, as is detailed in a subsequent chapter, that raps (we are dealing at present only with that phase) are caused by a protrusion from the medium's person of a long rod of a substance having certain properties which distinguish it from all other forms of matter. This substance has been closely examined by the great French physiologist, Dr. Charles Richet, who has named it "ectoplasm." These rods are invisible to the eye, partly visible to the sensitive plate, and yet conduct energy in such a fashion as to make sounds and strike blows at a distance.

from http://gutenberg.net.au/ebooks03/0301051h.html

  • Was a photographic plate mentioned earlier? Apr 1, 2020 at 10:56
  • @Fivesideddice no. but Photographic plate was very close
    – solesoul
    Apr 1, 2020 at 10:58

1 Answer 1


In 1859, when Conan Doyle was born, the term 'sensitive plate' was just starting to be used to describe a glass plate coated with light-sensitive chemicals. The term was still in use in 1888 when this edition of the Photographic News was published but, as this NGram graph shows, from then on the term was quite rapidly overtaken by 'photographic plate'.

Conan Doyle published the collection of essays "The history of spiritualism" in 1926. The term 'sensitive plate' was still in use but 'photographic plate' was nearing its peak, however Conan Doyle was nearly seventy by then, and can perhaps be forgiven for using the older term.

  • 1
    It's even more confusing to the modern reader because ACD's subject matter here includes repeated references to sensitive as a noun usage (meaning people who are sensitive to paranormal phenomena). Given that photographic technology wouldn't have been familiar to many readers, they'd naturally be inclined to interpret sensitive plate as specifically implying plate capable of / designed for capturing images of the supernatural that are normally invisible. Perhaps ACD chose to use that slightly odd term specifically for that reason. Apr 1, 2020 at 11:58
  • Note that Conan Doyle was born in 1859. The History of Spiritualism was first published in 1926 (by which time "the sensitive plate" was way past its sell-by date! :) Apr 1, 2020 at 12:24
  • @FumbleFingersReinstateMonica, oops... I read the wrong date from the web site. Thank you for pointing that out: I have updated my answer.
    – JavaLatte
    Apr 2, 2020 at 0:13

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .