Showing posts with label microscope. Show all posts
Showing posts with label microscope. Show all posts

Tuesday, June 12, 2007

Drinking Cup Sediment Kills a Pig

1910

CHICAGO — Public drinking cups are dangerous. They are excellent mediums for transmitting the germs of disease. Especially is this true in public and parochial schools where a large number of children are compelled to use the same cups, according to the health bureau.

Statistics show about one person in sixty has tuberculosis, and among school children there always are those who have some of the communicable diseases in light form, and these undoubtedly are communicated by the use of the common cup.

So fully is this understood that several states have passed laws abolishing the public drinking cup, and compelling railroads and public carriers to supply individual ones. The plan also has been advocated in schools, but the better and safer plan is believed to be the installation of what are known as "bubbling" cups with the water flowing over the rims all the time.

A cup used in a high school for several months without having been washed was found to be lined inside with a thick brownish deposit. Under the microscope this deposit proved to be composed of particles of mud, thousands of bits of dead skin, and millions of bacteria. Some of this sediment was injected under the skin of a healthy guinea pig and forty hours later the pig died. An examination afterward showed that pneumonia germs had caused death. A second guinea pig was inoculated with some of the sediment from the same cup and developed tuberculosis. Careful inquiry showed that several pupils in this school from which the cup was taken were then suffering from consumption.

An agitation is urged asking the school board to install the "bubbling" cups in all schools.

Monday, May 7, 2007

The Germ Theory — Daniel Defoe, Journal of the Plague Year

1903

Defoe Gave a Hint of It In the Early Eighteenth Century

Defoe's "Journal of the Plague Year," published in 1722, contains two passages which grope toward bacteriology. Defoe himself pretends to disbelieve the theories. But his way is to seem to doubt what he is really eager to advance.

Having shown that contagion was almost certain in the case of people living in the same house, but often avoidable by segregation and precaution against physical contact, Defoe says:

"This put it out of question to me that the calamity was spread by infection — that is to say, by some certain steams or fumes, which the physicians call effluvia, which effluvia affected the sound who came within certain distances of the sick. Others talk of infection being carried on by the air only by carrying with it vast numbers of insects and invisible creatures, who enter into the body with the breath or even at the pores with the air and there generate or emit most acute poisons or poisonous ova or eggs, which mingle themselves with the blood and so infect the body."

In another place is this passage:

"I have heard it was the opinion of others that it (the disease) might be distinguished by the party's breathing upon a piece of glass, where, the breath condensing, there might living creatures be soon by a microscope of strange, monstrous and frightful shapes, such as dragons, snakes, serpents and devils, horrible to behold. But this I very much question the truth of, and we had no microscopes at the time, as I remember, to make the experiments with."

Friday, May 4, 2007

What the Microscope Reveals

1878

Mold is a forest of beautiful trees, with the branches, leaves and fruit.

Butterflies are fully feathered.

Hairs are hollow tubes.

The surface of our bodies is covered with scales like a fish; a single grain of sand would cover one hundred and fifty of these scales, and yet a scale covers five hundred pores. Through these narrow openings the perspiration forces itself like water through a sieve.

Each drop of stagnant water contains a world of living creatures, swimming with as much liberty as whales in the sea.

Each leaf has a colony of insects grazing it, like a cow in a meadow. — Exchange.


Words of Wisdom

It is easier to blame than to do better.

If you wish to succeed in life, govern your temper.

We love much more warmly by cherishing the intention of giving pleasure than an hour afterwards when we have given it.

If a man be gracious and courteous to strangers, it shows he is a citizen of the world, and that his heart is no island cut off from other hearts, but a continent that joins them.

The last, best fruit which comes to late perfection, even in the kindliest soul, is tenderness toward the hard, forbearance toward the unforbearing, warmth of heart toward the cold, and philanthropy toward the misanthropic.

Sunday, April 22, 2007

Microscopic Writing: Eight Bibles to the Square Inch

1895

MICROSCOPIC WRITING

The Wonders That May Be Accomplished In a Square Inch of Space

Among the collection of microscopic objects in the United States Army Medical museum at Washington is a specimen of microscopic writing on glass which contains the Lord's Prayer, written in characters so small that the entire 227 letters of that petition are engraved within an area measuring 1-294 by 1-441 of an inch.

So far this statement does not trouble us. If, however, we go a little further, we easily find that the area having the above dimensions would be only the 1-129,654 of a square inch, and consequently that an inch square covered with writing of the same size, or counting 227 letters to each such fraction, would contain 29,431,458 letters.

Let us put this figure into a concrete form by seeing how much of a book this number of letters would represent. The Bible is a book of which we may safely assume that every one has an approximate idea as regards its general size or extent. Some one has actually determined the number of letters contained in the entire Old and New Testaments and finds this to be 3,566,480. Hence the number of letters which a square inch of glass would accommodate, written out like the text of the Lord's Prayer on this strip of glass, is more than eight times this last number, or, in other words, a square inch of glass would accommodate the entire text of the Bible eight times over written out as is the Lord's Prayer on this strip of glass.

I am free to confess that, though this fact has been known to me since 1873, and I have had in my possession photographs taken with the microscope of this writing, I cannot say that I fully apprehend or mentally grasp the fact just stated. I can form no mental picture of a square inch of glass with the entire text of eight Bibles engraved upon it, and yet when I have verified the measurements and calculations leading up to this conclusion I feel absolutely certain as to its truth, not as the result of intuition, but as a deduction from experience which has not yet developed into an intuitive consciousness. — Dr. Henry Morton in Cassier's Magazine.