Silica and Sleep
A popular song recorded in 1954¹ begins with, "Mr. Sandman, bring me a dream." An old nursery rhyme says, "The Sandman's coming in his train of cars / With moonbeam windows and with wheels of stars."
Both of these verses are about the mythical Sandman of folklore in Northern Europe. The imaginary Sandman caused people to sleep, then sprinkled magical sand on them to bring good dreams. The "sand" in the stories refers to grainy particles most people have in...
What's New in Box Springs?
For many of us, the box spring is a Ho-Hum item. We buy a mattress, and a box spring is included. When the new mattress is delivered and set up, the box spring is placed on the rolling steel frame, which is adjusted for fit. Then the new mattress is placed on the new box spring. We think we know what a box spring is, so we just take it for granted.
The truth is, that plain old box spring under our bed might not be as old a design as we think. It may be something...
Progressive Rate Springs:
What Are They Doing in My Bed?
If anyone of us knows what progressive rate springs (PRS) are, the first place we expect them is in wheeled vehicles. In fact, that is the intended application of progressive rate coiled springs, and that is what comes up first in an online search. So it surprising to find "progressive rate springs" in the description of a mattress. And a waterbed mattress, no less!
Before we go on, let's see what a progressive rate spring is. Some...
The smallest mattress coils so far
It used to be that the shortest mattress coils were the 4" Bonnell coils in a sofabed mattress. The reason they were so short, when most coils were 7 or 8 inches high, was so the mattress could be folded to fit inside the sofa under the seat cushions.
With the introduction of pocket coils, the trend was for innerspring coils, at least the wrapped coils, to become taller, up to 9 or 10 inches. This allowed greater conformabiity and more...
Minicoils or Microcoils?
A previous blog article, Microcoils, covered the use of coils in mattresses that are significantly smaller than innerspring coils. In this article, I noted that some of these smaller coils are much smaller than others, and that there has not been a concensus on terminology.
Until now, the whole category of small springs has been classified as microcoils. But now several manufacturers are placing two layers of these coils above the support core of a mattress....
What Are You Sleeping on?
The Ingredients List for Mattress Recipes
What are you sleeping on? A few of the readers of this article may sleep in a sleeping bag or on folded blankets or quilts on a sleeping mat or an air mattress, especially if they are camping at the time and using a smart phone or tablet. Most of us, however, sleep on beds of one sort or another, also including sofas, futons, semi sleepers, and built-in beds.
The most common configuration for a bed in North America is a...
Divans and Ottomans:
The Alternate Foundations
We in North America (United States and Canada) are conditioned to think of divans as some kind of couch or sofa which may or may not have armrests at the ends. Thus we are initally puzzled when a divan is one of the foundations available for a mattress. However, the two usages are related. After all, many people will stretch out on a divan for a nap.
Ottomans, likewise, come from across the Atlantic with a different application than what we...
Pocket (Marshall) Coils
[caption id="attachment_731" align="aligncenter" width="300"] Pocket coils Image from Simmons Beautyrest[/caption]
Pocket coils, also known as pocketed coils, encased coils, wrapped coils or Marshall coils, are light gauge open-end coils in fabric pockets. They were invented in 1900 by James Marshall, an Englishman who migrated to Canada. In Toronto, Ontario, Canada he founded the Marshall Mattress Company to make mattresses using his technology. The company is...
[caption id="attachment_719" align="aligncenter" width="347"] Looking down rows of continuous coils Image from Bedrooms & More, Seattle, Washington[/caption]
Continuous coils are the least expensive type of coils used in innerspring mattresses. According to Seattle Mattress Company, this coil type was invented by Serta. Currently, Serta is the largest user of continuous coils. Serta's continuous coils are manufactured by Leggett & Platt under the trade name...
Offset (Karr) Coils
[caption id="attachment_705" align="aligncenter" width="642"] Offset Coil System Image from Bedrooms & More, Seattle, Washington[/caption]
Offset coils, also called Karr coils, were invented in the early 1900s by Frank Karr, who also started the Spring Air mattress company. They were developed from Bonnell coils, the original support for innerspring mattresses. Since the inception of offset coils, they have been used by many other mattress companies.