Ask the Scholar
Page 2 of 2
I can add historical knowledge about this page.
Page image
OCR
February 23, 1940.
Memorandum to: Doctor F. B. Flinn
Subject: Radio-active Film
Mr. Gordon and I have discussed the status of the above problem,
and he suggests that I outline the progress for you.
We have at the present time an experimental film which provides con-
siderable alpha radiation and appears to possess the properties you require.
Altho we have not subjected it to hard usage, the active deposit seems to be
firmly attached, a factor we determined by a series of gamma ray measurements
which indicate also that the emanation is not being released, but decays in
the film and would therefore be effective for your work. The quantitative
alpha ray measurements have not been completed, and will probably require
several weeks more. Our measuring equipment requires some modification, and
until it functions satisfactorily we will not be able to determine the success
of our work. Rough preliminary work indicates that we are obtaining perhaps
20% to 25% efficiency, but this figure is subject to considerable modification.
Because of the nature of this film, we would not care to release it for
use until we are more certain that it is fool-proof. A film such as we originally
discussed can be prepared. However, even such a film should be measured care-
fully before released to forestall the possibility of its failure to work success-
fully being attributed to the wrong factors. Here again, we must wait for the
completion of our measurement equipment, unless you would oare to do your pre-
liminary work and make the activity determinations later. If you prefer to
take this course, we will prepare the film immediately and give you the results
of our experimental work later.
Page data
- Page
- 2
- Source index
- 0
- Type
- document
- Media ID
- 47b11a953a18fb45
- Size
- unknown
Document data
- ID
- 75729719
- Core
- doc
- Type
- document
DTO data
{
"id": "75729719",
"sourceUrl": "https://catalog.archives.gov/id/75729719",
"contentType": "document",
"title": "Letters Sent to Dr. F.B. Flinn [Dr. Frederick B. Flinn], February 23, 1940",
"citationUrl": "https://catalog.archives.gov/id/75729719",
"collections": [
"Safety Light Collection",
"Records Related to Radium Dial Painters"
],
"iiifBase": "https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/SLC/Radium/SLC_0003431.jpg",
"thumbnailUrl": "https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/SLC/Radium/SLC_0003431.jpg",
"largeImageUrl": "https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/SLC/Radium/SLC_0003431.jpg",
"imageCount": 2,
"hasImages": true,
"source": "import",
"hasTranscription": false
}
Context sent to Scholar
Document identity
{
"localId": "75729719",
"label": "Letters Sent to Dr. F.B. Flinn [Dr. Frederick B. Flinn], February 23, 1940",
"core": "doc",
"dtoType": "document",
"citationUrl": "https://catalog.archives.gov/id/75729719"
}
Document source metadata
{
"id": "75729719",
"sourceUrl": "https://catalog.archives.gov/id/75729719",
"contentType": "document",
"title": "Letters Sent to Dr. F.B. Flinn [Dr. Frederick B. Flinn], February 23, 1940",
"citationUrl": "https://catalog.archives.gov/id/75729719",
"collections": [
"Safety Light Collection",
"Records Related to Radium Dial Painters"
],
"iiifBase": "https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/SLC/Radium/SLC_0003431.jpg",
"thumbnailUrl": "https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/SLC/Radium/SLC_0003431.jpg",
"largeImageUrl": "https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/SLC/Radium/SLC_0003431.jpg",
"imageCount": 2,
"hasImages": true,
"source": "import",
"hasTranscription": false
}
Document source extras
{
"url": "https://catalog.archives.gov/id/75729719",
"naId": 75729719,
"levelOfDescription": "fileUnit",
"recordType": "description",
"ocrSource": "nara-archive"
}
Page context
{
"seq": 2,
"pageIndex": 0,
"type": "document",
"url": "https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/SLC/Radium/SLC_0003431.pdf",
"mediaId": "47b11a953a18fb45",
"ocrText": "February 23, 1940.\nMemorandum to: Doctor F. B. Flinn\nSubject: Radio-active Film\nMr. Gordon and I have discussed the status of the above problem,\nand he suggests that I outline the progress for you.\nWe have at the present time an experimental film which provides con-\nsiderable alpha radiation and appears to possess the properties you require.\nAltho we have not subjected it to hard usage, the active deposit seems to be\nfirmly attached, a factor we determined by a series of gamma ray measurements\nwhich indicate also that the emanation is not being released, but decays in\nthe film and would therefore be effective for your work. The quantitative\nalpha ray measurements have not been completed, and will probably require\nseveral weeks more. Our measuring equipment requires some modification, and\nuntil it functions satisfactorily we will not be able to determine the success\nof our work. Rough preliminary work indicates that we are obtaining perhaps\n20% to 25% efficiency, but this figure is subject to considerable modification.\nBecause of the nature of this film, we would not care to release it for\nuse until we are more certain that it is fool-proof. A film such as we originally\ndiscussed can be prepared. However, even such a film should be measured care-\nfully before released to forestall the possibility of its failure to work success-\nfully being attributed to the wrong factors. Here again, we must wait for the\ncompletion of our measurement equipment, unless you would oare to do your pre-\nliminary work and make the activity determinations later. If you prefer to\ntake this course, we will prepare the film immediately and give you the results\nof our experimental work later."
}