« PředchozíPokračovat »
The oxidation of the alcohol vapor keeps the disk hot, and this being so near the surface of the alcohol, heats it to such an extent as to completely vaporize one gallon of alcohol in from one and a half to two hours, smaller quantities in proportionately less time. The gas is in a highly heated condition and as it rises it impinges against the under surface of the water pan and begins to heat the water. However, a large volume of gas is thrown off before the water vapor begins to be evolved. As shown in the reaction, CH ̧0+0=CH2O+H2O, there is liberated in the production of 30 parts of formaldehyde, 18 parts of water, or for 40 parts of formaldehyde 24 parts of water; while when the gas is liberated by heating the aqueous solution, for every 40 parts of gas there are liberated 60 parts of water, most of the water being introduced into the apartment before the formaldehyde, as previously described. The heat produced by the oxidation of the alcohol also perceptibly warms the atmosphere of a room and thus decreases the amount of condensation of the water vapor which occurs. I am quite positive also that by this method there is less polymerization of the formaldehyde gas and therefore the odor after disinfection. is much less persistent.
The use of the vessel in the upper portion of the apparatus is for the purpose of burning sulphur when desired. While formaldehyde is by far the most efficient of the two gases for the destruction of micro-organisms, sulphur dioxide is more efficient in the destruction of insect life, mosquitoes, etc. Therefore, when it is desired to combat insect borne diseases-malaria, yellow fever, etc., the fumes of burning sulphur can be produced. Both formaldehyde and SO, can be generated simultaneously with great advantage in many cases without any interference chemically with each other. What virtue the addition of the carbolic acid to the alcohol may have I am not yet certain; but actual experiment has shown that carbolic acid is volatilized and I am inclined to the belief that it increases the germicidal value of the formaldehyde. Further experiments will be made to determine this point. During the bacteriological experiments made by Dr. Smith and Dr. Ter
rill, the report of which is here appended, it was thought that it might be of value to make a determination of the volume of gas in the apartment at the end of stated intervals. Accordingly, however, in series 4 the generator was charged with 1,500 c. c. of alcohol and phenol mixture and definite quantities of the air aspirated at the end of one and two and three hours after the machine was put in operation, through a standard solution of ammonia and the amount of ammonia not neutralized determined by titration with standard acid, and from the data obtained the amount of gas by volume calculated. This method is in general use, although there are a number of possible errors incident to it, but I will give the results for what they are worth. The values so obtained are often quite discordant. If the results are to be relied upon then this method of generating formaldehyde is a very efficient one for the reason that most authorities state that two per cent by volume is necessary to effectually destroy pathogenic organisms after several hours exposure. At the end of one hour by the method mentioned I found the atmosphere to contain 1.6 per cent by volume of formaldehyde, at the end of two hours 0.95 per cent, and at the end of three hours 0.75. Now, since in series No. 3, where sterilization was effected with 750 c. c. of alcohol in from three to six hours, the percentage must have been less than half of the amounts present in series 4, and yet the results were all to be desired. From the experiments made by Dr. Smith and Dr. Terrill and from others made by myself in a room of about 2,500 cubic feet capacity I have found that from 750 c. c. to 1,000 c. c. can be relied upon to disinfect a space of 1,000 cubic feet, in from three to six hours. That the atmosphere of the room was saturated in series 4 was shown by the fact that moisture condensed copiously upon the window glass.
The advantages of the device may then be summarized as follows: The short time required for sterilization owing to the rapid evolution of the gas, cheapness of operation, simplicity, requiring only a few minutes of one's time to set it in operation and then requiring no further attention, and finally the convenience.
The results of the bacteriological tests are appended.
THE OCCURRENCE OF TAENIA NANA IN TEXAS (THE FIRST OR AT LEAST THE SECOND REPORTED CASE IN NORTH AMERICA).
JOHN T. MOORE, M. D.
Associate in Clinical Medicine, University of Texas, Medical Department, and Surgeon G., H. & H. Ry., Galveston.
I take this opportunity of presenting to this Association a case that is of quite rare occurrence in this country.
On August 2, 1902, a section foreman who works for the Galveston, Houston and Henderson Railway consulted me for a severe diarrhea, great weakness and cramps in the abdomen.
He was given a diarrhea mixture and asked to return in case he was not relieved. He came back on August 4th, stating that he was no better.
I suspected from the history that he was suffering from amoebic dysentery or some intestinal worm, and asked him to go to the infirmary where he could receive the proper care and have the stools examined.
I gave instructions to save all the stools passed and to examine carefully for all intestinal parasites and their ova.
Dr. J. R. Elliott, interne at St. Mary's Infirmary, to whom is due the credit of first finding the ova, reported that he had found the ova of some tapeworm that he thought fit the description of tænia nana.
We went over the examination very carefully together and soon became convinced that we had the ova of tænia nana.
I ordered an anthelmintic given, and instructed them to save everything passed. Much time was spent in washing the stool through a muslin cloth, but without finding anything. I now adopted the plan of putting small quantities of the fecal material
in a clear glass beaker filled with water. We were soon rewarded by finding pieces of the worm. We washed quite a good deal of the material, hoping to find the whole worm, or at least the head, but were unsuccessful.
I submitted specimens to Dr. C. W. Stiles, Chief of the Division of Zoology, Washington, and to Dr. A. J. Smith, Professor of Pathology, University of Texas, for identification. They very promptly verified our diagnosis of hymenolepis (tænia nana), as shown by their notes, which I here publish:
WASHINGTON, D. C., August 28, 1902. Referring again to your letter of August 9th, I would state that the specimens have been stained and mounted. Unfortunately, the material is in a poor state of preservation, so that it was impossible to make any very minute observations upon it. Nevertheless, sufficient was seen to lead me to believe that you are safe in classifying the tapeworm as tænia nana, or, according to the more modern classification of tapeworm, as hymenolepis nana (Siebold, 1852).
GALVESTON, TEXAS, September 10, 1902. The specimen of tapeworm links sent me today, with request to confirm or correct your identification as tænia nana, has been examined.
I am confident of the correctness of your diagnosis.
The specimen is extremely rare, and its occurrence here should be reported for record.
ALLEN J. SMITH.
CASE: T. O. C. Occupation, section foreman in G., H. & H. Ry. yards; residence, Galveston; single; age 35 years; born in Ireland.
Family History: Father died at age of 68; mother died at about the same age. Previous health of both parents good. Four brothers and four sisters living and in good health.
Personal History: Drinks beer and gets drunk now and then. Smokes tobacco.
Previous Residence: Came from Ireland to Sedalia, Mo., in 1879, passing through Boston. He lived at Sedalia eighteen months, working on the railroad tracks in the yards there. From Sedalia he came to Texas, stopping first at Laredo, thence to Waco,
Dallas, Longview, Palestine, and San Antonio. He worked at Cleburne, Texas, four or five months during 1882, and at Houston most of 1883. From 1883 to 1891 he was working at Galveston or in that vicinity. In 1892 he worked on the Galveston jetties. He worked on the Santa Fe Railway near Arcola, Texas, during 1893. In 1894 he was working on the Alta Loma pipe line, the line furnishing Galveston her water supply from artesian wells eighteen miles away. Worked on city railroad during 1895; after this he went to Houston for three years, thence back to Galveston in 1900, where he has since lived. During all of this time he says that his health was perfect.
Present Disease: Two months before entering hospital, which was on August 4, 1902, he felt feverish, especially during the mornings, and had considerable headache at times. He would be well for two or three days and then get sick again. Appetite was good, and bowels regular during this time.
One week before consulting me (July 28, 1902), he was taken with a severe diarrhea. The bowels would move eight or ten times during the day and as often during the night. There was considerable pain in the belly about the umbilicus. He passed much blood and mucus; appetite poor. He complains now (August 3rd) of pain in belly, diarrhea, and great weakness.
Present Condition: He is a tall man, height six feet, weight about 150 pounds, rather sparely built; temperature 101° F.; pulse 110; respiration 18. Heart and lungs normal. Liver and spleen a little enlarged. Some tenderness over stomach and abdomen.
Some intestinal parasite was suspected, and he was advised to enter the hospital, which he did August 5, 1902. The blood examination for malarial parasites was negative.
August 5th. The patient passed a very restless night. The bowels moved about twenty times during the past twenty-four hours. The stools were examined by Dr. J. R. Elliott, who reported. finding the ova of some intestinal worm, probably tænia nana.