Dust and Microbes.

Otago Witness, Volume 26, Issue 2419, 26 July 1900, Page 58

Dust and Microbes.

There is an intimate connection between dust end microbes, and a correspondent versed in the matter sends a communication o.\the subject to t^ie Westminster Gazette. W/ier-e dust is present in the air microbes are J'hsre also, though not in the same numbers a' 4 the dust particles. If, therefore, we wtmt £o avoid ;microbss«, we should draw the air supply for our houses, churches, or theatres from above the dust level : —

"It is not commonly known that in a London street the number of dust particles in a wineglassful of '.clean breathing , air ' is about 30,000,000, whereas at .the level of the second floor -the number is three times lesrf, facts of which advantage is taken in modern methods of ventilation. Nevertheless, as only 20 out of the 600 krown bacteria are hostile to man, and of these 20 only a few have their habitat in the air, we mtast not attach any- exaggerated importance to their presence. What is important is 'du&t."

It is iisii.il to provide a good exit for used sir, up the chimney or otherwise, without taking any precaution to wash or filter that which enters; yet the air reaches a more delicate internal organ than bread, meat, or drink, which we are parliculrr to have clean.

To avoid rebreathing, and to keep all duss, from a brge congregation from reaching^ the level of the lips, would, our correspondent goes on to say, have been an expensive matter 10 years ago ; it- is so no longer. One mare flue in a modern house suitably placed for the down w aid flow of. warm "filtered air into the hall wilL be a cheap commonplace in 30 years ; " In dwellings there are usually few persons per room, and few rooms are inhabited for hours on end, but in places of meeting and picture galleries, to give every person 1000 cubic feet of air per hour is a question of public health of the highe&t importance. The entire mechanism to filter, moisten, warm, cool, control, admit, and carry off without draught 1,000,000 cubic feet of air per hour would cost about JBSOO, yet we are air-starved in almost all our museums, chuvehes, and picture galleries, where one hour's visit will procure greater exhaustion from this cause than two hours' hard woik in the studio."