May 7, 2022 05:57 PM
(This post was last modified: May 7, 2022 08:19 PM by C C.)
Wood ash cement & fired brick hut (primitive architecture)
https://youtu.be/eesj3pJF3lA
INTRO (Primitive Technology): I built a hut from fired clay bricks and mortared them together with a cement made from wood ash left over from the firing process. When I developed wood ash cement years ago in a previous video, it was in response to the need of a cement made from material other than lime stone, which is absent in my location. Wood ash was suitable because it contains calcium oxide, the active cementitious material for making mortar. I made clay bricks and fired them in a kiln made previously.
Then I collected the wood ash and made them into pellets storing them for later use. When it was time to make the mortar, I put the pellets in the kiln and fired them. Here it's important to note that the ash needs to be fired at a high temperature with oxygen, ordinary ash from a camp fire won't work as is because they don't get hot enough. It needs to be pelletized and fired again in a kiln before use.
I mixed the fired ash pellets with sand (1:3 ratio by volume) and used it to mortar the bricks together. It's important to use a trowel (flat piece of wood here) instead of bare hands to handle the mortar due to lye burning the skin (I got mild lye burns on my fingers). The ash left over from firing the bricks was enough to mortar those same bricks together.
The hut was 2x2 m and 2 m high at the gables. Wooden beams were placed onto the gables to form the roof and secured in place with mortar. Then I made barrel roof tiles and lay them onto these beams. The whole project took 6 and a half months to build.
The hut sheds rain well and the mortar is water proof (won't dissolve in water), surviving many rainstorms even before the roof was up. The main take away from this video is to always look for a way to take a waste material (wood ash) and make it into a resource (cement).
May 5, 2022 - Primitive Technology: "Wood ash cement & fired brick hut"
https://www.youtube-nocookie.com/embed/eesj3pJF3lA
Innovative fish farms feed people, save jobs, and clean up an industry’s dirty reputation (design, engineering)
https://www.scientificamerican.com/artic...eputation/
EXCERPTS: . . . The truth is that soon fish farming may be the only way for Maine’s struggling seafood workers to make any bucks at all. Thanks to overfishing, parasites and rising ocean temperatures, among other threats, nearly all of Maine’s commercial fisheries are in free fall.
Maine cod is crashing, as are local shrimp. The wild mussel catch declined from 25 million pounds to a mere nine million over the past two decades. And lobsters, by far the state’s most profitable catch, are scuttling north to cooler Canadian waters.
None of this bodes well for the state’s once robust seafaring economy: the average age of a Maine commercial fisher hovers above 50, suggesting that many young people have lost faith in the work.
As one wild fishery after another falters, the future of Maine—and, some say, the future of seafood—may lie in aquaculture, the cultivation of aquatic plants and animals. Historically, intensive fish farms have been linked to a lot of bad things: declines in biodiversity, habitat loss, the overuse of antibiotics, and animal welfare abuses, especially in Asia and Latin America. And in recent years fish die-offs and other problems have plagued North American sites.
But Newell represents a new breed of scientist with innovative approaches to growing fish that are both economically and environmentally sustainable. His kludgy mussel-growing apparatus generates three times as much seafood as traditional mussel farms. And because free-floating mussel larvae seed the ropes naturally and eat whatever phytoplankton drifts their way, Newell’s farms require no human-generated feed or energy, a boon for the environment as well as for his bottom line.
[...] For decades the U.S. fishing industry has struggled to harvest enough wild fish to meet the growing demand—we want cheap fish, and we want it now. The shocking decline of Maine’s commercial wild fisheries shows that this approach no longer serves us.
Farmed finfish is generally cheaper than wild, and many restaurateurs consider farmed bivalves tastier than a lot of wild varieties. Farmed versions of all fish are generally more widely available, regardless of the season.
It is too soon to say whether aquaculture can bolster Maine’s fragile seafaring sector or contribute significantly to its economy without disrupting the state’s iconic shoreline; large finfish facilities, such as RAS, create additional concerns about energy use and animal well-being. But to many scientists, economists and policy makers, one thing is becoming clear: farming fish sustainably in concert with other animals and plants will likely be the best approach to feeding the world’s population in the years and decades ahead.. (MORE - many missing details)
https://youtu.be/YGaFNZzjCXI
https://www.youtube-nocookie.com/embed/YGaFNZzjCXI
https://youtu.be/eesj3pJF3lA
INTRO (Primitive Technology): I built a hut from fired clay bricks and mortared them together with a cement made from wood ash left over from the firing process. When I developed wood ash cement years ago in a previous video, it was in response to the need of a cement made from material other than lime stone, which is absent in my location. Wood ash was suitable because it contains calcium oxide, the active cementitious material for making mortar. I made clay bricks and fired them in a kiln made previously.
Then I collected the wood ash and made them into pellets storing them for later use. When it was time to make the mortar, I put the pellets in the kiln and fired them. Here it's important to note that the ash needs to be fired at a high temperature with oxygen, ordinary ash from a camp fire won't work as is because they don't get hot enough. It needs to be pelletized and fired again in a kiln before use.
I mixed the fired ash pellets with sand (1:3 ratio by volume) and used it to mortar the bricks together. It's important to use a trowel (flat piece of wood here) instead of bare hands to handle the mortar due to lye burning the skin (I got mild lye burns on my fingers). The ash left over from firing the bricks was enough to mortar those same bricks together.
The hut was 2x2 m and 2 m high at the gables. Wooden beams were placed onto the gables to form the roof and secured in place with mortar. Then I made barrel roof tiles and lay them onto these beams. The whole project took 6 and a half months to build.
The hut sheds rain well and the mortar is water proof (won't dissolve in water), surviving many rainstorms even before the roof was up. The main take away from this video is to always look for a way to take a waste material (wood ash) and make it into a resource (cement).
May 5, 2022 - Primitive Technology: "Wood ash cement & fired brick hut"
Innovative fish farms feed people, save jobs, and clean up an industry’s dirty reputation (design, engineering)
https://www.scientificamerican.com/artic...eputation/
EXCERPTS: . . . The truth is that soon fish farming may be the only way for Maine’s struggling seafood workers to make any bucks at all. Thanks to overfishing, parasites and rising ocean temperatures, among other threats, nearly all of Maine’s commercial fisheries are in free fall.
Maine cod is crashing, as are local shrimp. The wild mussel catch declined from 25 million pounds to a mere nine million over the past two decades. And lobsters, by far the state’s most profitable catch, are scuttling north to cooler Canadian waters.
None of this bodes well for the state’s once robust seafaring economy: the average age of a Maine commercial fisher hovers above 50, suggesting that many young people have lost faith in the work.
As one wild fishery after another falters, the future of Maine—and, some say, the future of seafood—may lie in aquaculture, the cultivation of aquatic plants and animals. Historically, intensive fish farms have been linked to a lot of bad things: declines in biodiversity, habitat loss, the overuse of antibiotics, and animal welfare abuses, especially in Asia and Latin America. And in recent years fish die-offs and other problems have plagued North American sites.
But Newell represents a new breed of scientist with innovative approaches to growing fish that are both economically and environmentally sustainable. His kludgy mussel-growing apparatus generates three times as much seafood as traditional mussel farms. And because free-floating mussel larvae seed the ropes naturally and eat whatever phytoplankton drifts their way, Newell’s farms require no human-generated feed or energy, a boon for the environment as well as for his bottom line.
[...] For decades the U.S. fishing industry has struggled to harvest enough wild fish to meet the growing demand—we want cheap fish, and we want it now. The shocking decline of Maine’s commercial wild fisheries shows that this approach no longer serves us.
Farmed finfish is generally cheaper than wild, and many restaurateurs consider farmed bivalves tastier than a lot of wild varieties. Farmed versions of all fish are generally more widely available, regardless of the season.
It is too soon to say whether aquaculture can bolster Maine’s fragile seafaring sector or contribute significantly to its economy without disrupting the state’s iconic shoreline; large finfish facilities, such as RAS, create additional concerns about energy use and animal well-being. But to many scientists, economists and policy makers, one thing is becoming clear: farming fish sustainably in concert with other animals and plants will likely be the best approach to feeding the world’s population in the years and decades ahead.. (MORE - many missing details)
https://youtu.be/YGaFNZzjCXI