Ask the Scholar

{
    "localId": "75723456",
    "label": "Letters Received to H.H. Barker, December 7, 1928",
    "core": "doc",
    "dtoType": "document",
    "citationUrl": "https://catalog.archives.gov/id/75723456"
}

{
    "id": "75723456",
    "sourceUrl": "https://catalog.archives.gov/id/75723456",
    "contentType": "document",
    "title": "Letters Received to H.H. Barker, December 7, 1928",
    "citationUrl": "https://catalog.archives.gov/id/75723456",
    "collections": [
        "Safety Light Collection",
        "Records Related to Radium Dial Painters"
    ],
    "iiifBase": "https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/SLC/Radium/SLC_0001538_Page_1.jpg",
    "thumbnailUrl": "https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/SLC/Radium/SLC_0001538_Page_1.jpg",
    "largeImageUrl": "https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/SLC/Radium/SLC_0001538_Page_1.jpg",
    "imageCount": 4,
    "hasImages": true,
    "source": "import",
    "hasTranscription": false
}

{
    "url": "https://catalog.archives.gov/id/75723456",
    "naId": 75723456,
    "levelOfDescription": "fileUnit",
    "recordType": "description",
    "ocrSource": "nara-archive"
}

{
    "seq": 2,
    "pageIndex": 0,
    "type": "photo",
    "url": "https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/SLC/Radium/SLC_0001538_Page_2.jpg",
    "mediaId": "18d6ca95d6d90217",
    "ocrText": "UNIVERSITY OF MISSOURI\nCOLUMBIA\nDEPARTMENT OF CHEMISTRY\n- 2 -\nH. H. BARKER\n3.\nGamma ray measurements were begun two days after the\nfirst bottle was ingested. Even then, when over 50 per cent of the radium\ningested had been eliminated, the gamma ray test was distinctly positive,\nand if we use a factor of the same order of magnitude as we use for the Wulf\ninstrument which we have been employing for gramma ray measurements, the radio-\nactivity by the gamma ray tests would exceed considerably the amount of\nradium and mesothorium still remaining in the system. In other words, I have\nconcluded that radium or mesothorium and its products when present in the\nintestinal tract, give a far greater gamma ray effect than we have assumed for\nour gamma ray measurements, and while we can only state approximately what\nthe magnitude of the effect is, I am beginning to feol that the factor to be\nused in converting scale readings to micrograms should be increased about\nfive fold when the gamma ray activity is localized in the intestines.\nI\nneed not point out the possible bearing of this result on the gamma ray\nmeasurements which Dr. Failla conducted last month. The relationship will\nbe quite apparent to you.\n4. An analysis of the residue of the faeces shows that\nmost of the activity is present in this residue. The first residue obtained\nabout two days after ingestion of the first bottle of Radithor contained at\nleast 60 per cent of the radioactivity, and the second residue contained\nfully 30 per cent, so that at least 90 per cent was recovered.\nI shall now repeat these experiments in somewhat modified\nform and in another week I hope to have a further set of experimental data to\nsubmit which I trust will corroborate in large part at least the conclusion\nherein stated.\nThis little experiment seems to me indicates that one can\neasily be made radioactive either by ingestion of radioactive water containing\nradon alone, or by radioactive water containing radium or mesothorium compounds\nin solution. We have thus far failed to detect thoron in the expired air,\nbut thoron is present apparently in normal amount in the faeces residue, and\nwhen a small part Of that is dissolved in dilute nitric acid and air bubbled\nthrough it into an electroscope, the discharge is surprisingly fast.\nIn addition to the repetition of this experiment, I would\nlike to try another to determine what sort of measurements one would get by\ningesting simply water containing radium emanation alone and not its parent\nsubstance, radium.\nI may add that a good many conjectures have passed through\nmy mind with reference to the bearing of this experiment on the observed dis-\ncrepancy in the activity of the five girls as found in Newark in April and in\nNew York very recently, but I do not have time now to begin writing out these"
}