Category Book of Knowledge – 1945

Pneumatic Tubes

Bran

As a child, I didn't particularly like having to ride along with my mom whenever she would drive to the bank, but one thing I did like were the tubes in the drive-through service bays. She would put her deposit slip and money in a garishly blue box, insert said box into an opening, push up slightly, and whoosh! Up it went! And then, many minutes later, the teller in the building would put my mom's receipt back in the box and send it back. It seemed amazing, particularly when I was younger, watching the box shoot upwards, gravity be damned, then curve towards and disappear into the building. If we were in the bay closest to the window, I could even watch the box descend down and land in its holding container. I have somehow remained ignorant of the name for this system of document transportation up until now. A post from The Onion today featured the phrase "pneumatic tubes" in its headline, and so I have the name now. And took a dive into my encyclopedias for more info on the matter.

The use of pneumatic tubes has assuredly declined in our digital society; the 1992 World Book, for instance, does not have an entry on them. The 1919 World Book, however, includes this entry for "pneumatic tubes" on page 4716 (volume 8):

PNEUMATIC TUBES, or PNEUMATIC DISPATCH, a system or method of sending mail, dispatches and parcels through tubes, either underground or above, by means of air pressure. In 1667 this method was first suggested by Denis Papin, who read a paper before the Royal Society of London explaining a device for sending a carrier containing mail through tubes by means of suction. Improvements on his suggestion, which were not commercially adopted until 1835, have led to the development of various forms of pneumatic transportation devices in every civilized country.

The necessary apparatus consists of a series of tubes, an air compressor and air-tight cylindrical carrying cases. The first pneumatic dispatch tubes installed only allowed the carriers to be sent in one direction, and to but one destination. This was improved upon by the use of alternate suction and pressure which allowed the carriers to travel both ways. This form was further modified by circular systems in which a current of air kept continually moving and the carriers could be withdrawn from the tubes at regular intervals or stations.

The pneumatic dispatch system has since 1870 proved successful in connection with the general post office, London, especially in the telegraph department, and there is now in use in this connection in that city a series of underground tubes over forty miles in length. The postal authorities and the telegraph companies in the United States have installed pneumatic dispatch systems in all large cities. Department stores and large retail stores in the States and in Canada employ the principle in tubes for conveying money from the counters to the cashier's desk. The development of pneumatic dispatch has not been so rapid in America as in Europe, but it is generally increasing, the system having been proved economical and efficient.

In pneumatic tubes of two and a quarter inches in diameter, worked with an air pressure of ten pounds per square inch, containing containers which hold seventy-five ordinary messenger forms, a speed is obtained in transit of a mile in two and one-half minutes. Large tubes for pneumatic dispatch, eight inches in diameter, are built for conveyance of carriers seven inches in diameter and twenty-four inches long. These tubes require an air pressure equal to thirty horse power, and the carriers are propelled through the tubes at the rate of thirty miles an hour.

Consult Batcheller's The Pneumatic Dispatch Tube System.

The diagram here is from the 1939 Comptons Pictured Encyclopedia, where it accompanies the entry on "pneumatic appliances" on page 266 of volume 11. The caption reads: This picture shows how the carriers travel back and forth in the tubes of a big store. When the carrier is inserted at any point in the system, it speeds forward until it strikes a trap door, which opens outward.
The door snaps open long enough to let out the carrier, but not long enough to let in much air. A suction fan is constantly exhausting the air from the pipes.

Large department stores are the subject of "The Wonder of a Great Store," an article features in volume 10 of The Book of Knowledge (1945). Although the article itself does not deal with the tubes, it is accompanied by a wonderful full-page photograph of a series of pneumatic tubes in the Macy's store in New York City, with the following caption: From almost every sales counter in the store a pneumatic tube runs, to carry the customer's money to a central desk, and to carry back change, if there is any, with hardly ever an error (p. 3679).

The above examples were arguably from reference works marketed towards children; we'll finish with some choice extracts from the 11th Edition Encyclopaedia Britannica and its entry on "pneumatic despatch" (volume 21, pp. 865-867). Get ready to get your math on - I had a lot of fun figuring out how to program the equations in \KaTeX.

PNEUMATIC DESPATCH, the name given to a system of transport of written despatches through long narrow tubes by the agency of air pressure. It was introducted in 1853 by J. Latimer Clark, between the Central and Stock Exchange stations of the Electric and International Telegraph Company in London. The stations were connected by a tube 1½ in. in diameter and 220 yds. long. Carriers containing batches of telegrams, and fitting piston-wise in the tube, were sucked through it (in one direction only) by the production of a partial vacuum at one end. In 1858 C. F. Varley improved the system by using compressed air to force the carriers in one direction, a partial vacuum being still used to draw them in the other direction. This improvement enables single radiating lines of pipe to be used both for sending and for receiving telegrams between a central station supplied with pumping machinery and outlying stations not so supplied.

[...] ...it is found more economical to transmit local message-work by tube rather than by wire, as skilled telegraphists are not required, but only tube attendants. [...]

The tubes are in all cases of lead...

Great care is exercised in making the joints in the lead pipes. Before the tube is placed in its trench a strong chain is passed through it, and a polished steel mandrel, 6 in. long and slightly less in diameter than the diameter of the tube, is heated and attached to the chain, and pushed half its length into the end of the tube already laid; the new length of tube is then forced over the projecting end of the mandrel until the tube ends (which have been previously cut flat) butt perfectly together; an ordinary plumber's joint is then made. By this means the tube is made perfectly air-tight, and the mandrel keeps the surface of the tube under the joint as smooth as at any other part of its length. After the joint is completed, the mandrel is drawn out by the chain attached to it, the next length is drawn on, and the above process repeated. The tubes are laid about 2 ft. below the surface of the ground.

The tubes radiate from the central to the branch offices, the principal offices having two tubes, one for "inward" and the other for "outward" traffic. At the smaller offices both the inward and the outward traffic is carried on through one tube. The "carriers" are made with gutta percha bodies, covered with felt, the front of the carrier being provided with a buffer or piston formed of several disks of felt which closely fit the tube; the messages are prevented from getting out of the carrier by the end being closed by an elastic band, which can be stretched sufficiently to allow the message forms to be inserted. The 3-in. carriers will hold 75 ordinary message forms, the 2¼-in. carriers 25 forms, and the 1½-in. carriers 20 forms. The carriers are propelled in one direction (from the central office) by "pressure," and drawn in the opposite direction by "vacuum," the standard pressure and vacuum being 10 ln and 6½ lb per sq. in. respectively, which values give approximately the same speed.

The time of transit of a carrier through a tube when the air pressure does not exceed 20 lb per square inch is given very approximately by the empirical formula: —

t=.00872\sqrt{\frac{l^3}{Pd}};

where l = length of tube in yards, d = diameter of tube in inches, P = effective air-pressure in pounds per square inch, t = transit time in seconds. For vacuum the formula is:—

t=\frac{.00825}{1 - .234\sqrt{15.5 - P_1}}\sqrt{\frac{l^3}{d}};

where P1 = effective vacuum in pounds per square inch.

The horse-power required to propel a carrier is approximately, for pressure:—

H.P. = (.574 + .0011P)\sqrt{\frac{P^3d^5}{l}};

for vacuum:—

H.P. = (5.187 - 1.214\sqrt{15.5 - P_1})P_1\sqrt{\frac{d^5}{l}}.

For a given transit time the actual horse-power required is much less in teh case of vacuum than in the case of pressure working, owing to the density of the air column moved being much less: thus, for example, the transit time for 10 lb pressure is the same as for 6½ lb vacuum, but the horse-power required in the two cases is as 1.83 to 1. [...] The transit time for a 2¼-in. tube is 16% more than for a 3-in. tube of the same length, when both are worked at the same pressure, but the horse-power required is 50% less; it is not advisable, therefore, to use a tube larger than is absolutely necessary to carry the volume of traffic required.

[...]

As a rule, only one carrier is despatched at a time, and no second carrier is inserted in the tube until the arrival of the first one at the farther end is automatically signalled (by an electric apparatus) to the despatching office. On some of the long tubes a carrier, when it passes the midway point in the tube, strikes a trigger and sends back an electrical signal indicating its passage; on the receipt of this signal a second carrier may be despatched. This arrangement has been almost entirely superseded by a signally apparatus which by a clock movement actuates an indicating hand moves the latter to "tube clear" a certain definite time (30 to 40 seconds) after a carrier has been inserted in the tube. By this arrangement carriers can be despatched one after the other at comparatively short intervals of time, so that several carriers (separated by distinct intervals) may be travelling through the tube simultaneously. It is necessary that the carriers be separated by a definite interval, otherwise they tend to overtake one another and become jammed in the tube. Although the stoppage of a carrier in a tube is of exceedingly rare occurance, it does occasionally take place, through picks being driven into the tube by workmen executing repairs to gas or water pipes, but the locality of such a stoppage is easily determined by a simple inspection along the route of the tube. In no case is any special means of testing for the locality from the central office found necessary.

[...]

The Book of Knowledge (1945)

Bran

General Details

Title: The Book of Knowledge
Volumes: 20 (bound into 10 books)
Language: English
Publisher: The Grolier Society Inc.
Year: 1945
Pages:7580

My copy of The Book of Knowledge: The Children's Encyclopedia is 20 volumes bound into 10. The books are copiously illustrated, with woodcuts, reproductions of artwork, photographs, and even a number of color plates. This set has a couple of similarities to the World Book volumes of that time: first, like The World Book, The Book of Knowledge underwent continuous revision, so no two printings are exactly alike. The volumes are also continuously numbered, so that volume 9/10, for example, contains pages 3025 to 3772.

This set is unlike other works featured on this site in that it is not arranged alphabetically. This is done purposefully, as mentioned in multiple prefatory essays, to encourage reading for pleasure. In the "The Purpose and the Plan" on page 9 it is stated: "The work has been planned, not so much to make learning easy, as to make it interesting. [...] The departments of The Book of Knowledge are distributed throughout the set, one or more sections appearing in almost every volume. This distribution has its root in sound psychology and has been found to be one of the strongest features of this work. The pedagogical reason is this: the average child can not concentrate long upon those subjects which require close attention. After a comparatively short period, he must change his occupation or rest." An article on the astronomical significance of the Earth is followed by one on the history and construction of bridges. After reading about fantastical creatures like the unicorn and sphinx, the reader is presented with an article on the Panama Canal. The "departments" of knowledge include "The Earth" (astronomy, geology, chemistry, physics, and meteorology), "Plant Life," "Animal Life," "Our Own Life," "Familiar Things," "Literature," "Stories," "Famous Books," "Wonder Questions," "All Countries," "The United States," "Canada," "Men and Women," "Golden Deeds," "Poetry," "Fine Arts," and "Things to Make and Things to Do."

This feature is repeatedly touted; in his introduction, John H. Finley writes: "It is not like a grown-up encyclopedia, a work of reference which one does not think of reading consecutively or for pleasure (though I have myself read through an encyclopedia of several volumes and found it intensely interesting and profitable reading). This is an encyclopedia in that it gives the child or youth possession of the whole cycle of existence and circle of truth to which he is entitled by birth. The city boy and the country boy find themselves inhabitants of a universe a thousand times more wonderful and interesting than that which most of their elders knew at their age or dreamed of. The facts of physics, biology, astronomy, history and language learned in these boyhood, girlhood days are never forgotten. Through them the child has inextricably woven into his being the life of the race and of the earth, who might otherwise be only a child of a certain valley or prairie, or of a certain street" (3).

Leonard Power's "A Unique Aid in Elementary Education" essay echoes the same sentiment - this set for children is superior to others precisely because it is not alphabetically arranged: "In its sheer power to delight children lies, I think, the greatest value of The Book of Knowledge. Rarely, indeed, are whole sets of books endowed with such power. Other reference works for children attain it to a degree corresponding with their willingness to break up the mechanically alphabetical continuity of their arrangement. But The Book of Knowledge has always held to the sound psychological arrangement appropriate for juveniles, yet providing a kit of tools (indexes) adequate for unlocking any particular door to knowledge" (8).

Sample Entries

To provide fair comparison between all of the works featured in my Reference Work Guide, I try to look up the same entries in each: "umbrella" and "Saint Louis." Due to the unique arrangement of topics in this work, I have to first consult volume 20. This final volume contains a general index, a chronology of the events of World War II, a poetry index, and the full texts of the Declaration of Independence and the U.S. Constitution. "Umbrella" has no entry in the general index, but "St. Louis" can be found on page 7458:

St. Louis. One of the greatest commercial centres in the U.S. 20 miles below the junction of the Missouri with the Mississippi, in Missouri. The river is crossed here by a bridge 2,225 feet long, connecting the city with East St. Louis. Finely built, the city has three cathedrals and two universities, but is famous chiefly for its great manufacture of tobacco, over 80,000,000 pounds of which are annually produced. Other industries include smelting, meat-packing, publishing, flour milling, foundries, and leather and clothing manufactures.
commerce and industries, 17-6046
fur-trading centre, 18-6426
iron and steel industry, 17-6038
Jefferson memorial, note and picture, 17-6047
scene of World's Fair (1904), 3-864
Pictures, 17-6047

Most of the St. Louis references come from an article in volume 17 on "The North Central States Part II" (pp. 6037-6048). St. Louis's iron industry is mentioned on page 6038: "St. Louis once had many blast furnaces. Ore was brought from Pilot Knob and Iron Mountain, a hundred miles away in the Ozarks. As late as 1880 St. Louis was spoken of as the 'City of the Iron Crown.' When the rich deposits of the Ozarks were exhausted the industry declined. Recently Roberts' coke oven, which makes excellent coke out of Illinois coal, has been invented. Across the Mississippi River from St. Louis coke ovens and blast furnaces have been erected. Ore can be secured either from Minnesota or from the rich deposits of Alabama, and a plan is under way to bring the Minnesota ore by way of the Mississippi River. The market for the product will be chiefly in the South and the Southwest. St. Louis may again become the 'City of the Iron Crown.'"

St. Louis is mentioned again later in the article in a section on the changing importance of river transportation in the region: "Commerce on the Mississippi River has come to be of less importance. There are several reasons. The railroads have been built with few curves from one important commercial centre to another. The winding pathway of the river increases the distance from one river port to another. Railroads can operate throughout the year. The Mississippi, especially above St. Louis, is closed to navigation for a part of the winter season. During the latter part of the summer season the water may be too low for the larger boats and barges, and the channel also shifts, and snags form. [...] Large sums have been spent to improve the navigation of the Mississippi and its tributaries, but without much plan. It is hoped that a complete plan will be worked out. The railroads took commerce away from the rivers, but they cannot always carry it all. The Federal Government has established a barge line between St. Louis and New Orleans, and modern docks have been built at St. Louis, Memphis and New Orleans. The Ohio River once had a very important commerce in coal and iron and steel products. Recently barges have brought iron and steel goods from Pittsburgh to St. Louis. It is expected that river boats will soon be making regular trips between St. Louis and St. Paul. Transporting heavy products like coal and iron by boat is economical; but we shall probably never see a return of the old days of bustling river traffic" (6040; 6044).

St. Louis is briefly compared to Chicago a couple of times in the article: "While Chicago is the largest meat-packing centre, other cities farther west, as St. Paul, Omaha, Kansas City and St. Louis, are also important. [...] In the early part of the last century, St. Louis was larger than Chicago, and Cincinnati was larger than Cleveland. Now, Chicago is over three times as large as St. Louis, and Cleveland is about twice as large as Cincinnati. The lake cities began to push ahead of the river cities when canals were built. One canal connected Cleveland with the Ohio River, another canal connected Chicago with the Illinois River. The lake cities reached out and captured commerce that had been going to the river cities" (6044; 6046). St. Louis then gets its own full paragraph, as well as a few photographs on the opposing page: "St. Louis was founded on the Mississippi River at a favorable site about twenty miles below the mouth of the Missouri River. Its location between the mouths of the Missouri and Ohio rivers gave it an early advantage when the rivers were the chief arteries of commerce. To-day the rivers are of less importance. St. Louis now has twenty-six railroad lines extending into its trade territory, and is called the gateway to the Southwest. Its location has made it a large wholesale centre. The food and allied products industry ranks next. St. Louis is very fortunate in that it manufactures so many different things that a business depression along a few lines does not affect it as much as it would affect many other cities" (6046).

The article from volume 3 is "The Story of Fairs" (pp. 858-864). Saint Louis is here mentioned briefly: Other noted American expositions include the following: The Pan-American Exposition at Buffalo in 1901; the St. Louis Exposition of 1904, celebrating the Louisiana Purchase, which reached a total attendance of 19,694,855 and cost $15,000,000; the Lewis and Clark Exposition at Portland, Oregon, in 1905; the Panama-Pacific Exposition, held at San Francisco from February to December, 1915, to mark the opening of the Panama Canal; and the Philadelphia Sesqui-Centennial of 1926" (864). Finally, St. Louis is briefly mentioned in volume 18's article "The Western States Part 1," in a section on fur-trading: "Having secured a large number of furs, the traders returned and sold then [sic] in cities or fur-trading posts. It was at this time that St. Louis became a fur-trading post. Even now the city of St. Louis is the centre of fur-trading in this country, although there are so many other larger industries in the city now that few people know that it is a fur centre" (6426).