On that form of chemical hygrometer in which sulphuric acid has been used as the absorbent : the Johnson memorial prize essay for 1891 / by M.S. Pembrey.

  • Pembrey, M. S. (Marcus Seymour), 1868-1934.
Date:
[1891]
Catalogue details

Licence: Public Domain Mark

Credit: On that form of chemical hygrometer in which sulphuric acid has been used as the absorbent : the Johnson memorial prize essay for 1891 / by M.S. Pembrey. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    With regard, secondly, to the rate of aspiration possible and the lasting powers of the tubes, we made a number of experiments. When a single absorption-tube was used, instead of the double ones described above, the absorption in the first tube was perfect (at least with rates up to two litres per minute) for a considerable time, as shown by the following experi- ments. Experiment No. 1. SO litres of air were aspirated at a rate of 1 litre per minute through two single absorption-tubes connected to- gether by a very short piece of rubber tubing. The aspirator in this and the following experiment was a glass filter-pump, the air being measured by a gas meter- Tube 1 .... -h 0-5142. Tube 2 .... +0-0000. Experiment No. 2. so litres aspirated at 1 litre per minute. Tube 1 . . . . +0-4712. Tube 2 .... +0-0002. Experiment No. 3. 50 litres aspirated at 1| litres per minute. Tube 1 . . . . +0-4057. Tube 2 .... +0-0001. Experiment No. 4. 21 litres aspirated at 2 litres per minute. Tube 1 . . . . +0-2334. Tube 2 .... +0-0C00. Experiment No. 5. 50 litres aspirated at 1 litre per minute. Tube 1 .... +0-4163. Tube 2 .... -0-0003. The same tubes were not used through all these experi- ments, as tube No. 1 had become spent in the middle of