Biodynamic agriculture

Biodynamic agriculture is a form of alternative agriculture very similar to organic farming, but which includes various esoteric concepts drawn from the ideas of Rudolf Steiner (1861–1925). Initially developed in the 1920s, it was the first of the organic agriculture movements. It treats soil fertility, plant growth, and livestock care as ecologically interrelated tasks, emphasizing spiritual and mystical perspectives.

Biodynamics has much in common with other organic approaches – it emphasizes the use of manures and composts and excludes the use of artificial chemicals on soil and plants. However, it goes further in a few respects, biodynamic farmers see their farm as an enclosed, self-sustaining organism. Methods unique to the biodynamic approach include its treatment of animals, crops, and soil as a single system; an emphasis from its beginnings on local production and distribution systems; its use of traditional and development of new local breeds and varieties; and the use of an astrological sowing and planting calendar and compost and field preparations meant to harness healing life forces which positively effect fertility on the farm.

As of February 2016, biodynamic techniques were used on 164,323 hectares in 64 countries with Germany accounting for 44% of the global total. Biodynamic methods of cultivating grapevines have been taken up by several notable vineyards. There are certification agencies for biodynamic products, most of which are members of the international biodynamics standards group Demeter International.

Biodynamic agriculture has only become the subject of scientific research within that last few decades, making scientific understanding of this farming method infant at best. Thus far, only preliminary beneficial outcomes have been scientifically established. Critics continue to characterized biodynamic agriculture as pseudoscience on the basis of a lack of strong evidence for its efficacy and skepticism about aspects criticized as being magical thinking., which highlights the importance of further scientific study.

History

Biodynamics was the first modern organic agriculture. Its development began in 1924 with a series of eight lectures on agriculture given by philosopher Rudolf Steiner at Schloss Koberwitz in Silesia, Germany, (now Kobierzyce in Poland southwest of Wrocław). These lectures, the first known presentation of organic agriculture, were held in response to a request by farmers who noticed degraded soil conditions and a deterioration in the health and quality of crops and livestock resulting from the use of chemical fertilizers. The one hundred eleven attendees, less than half of whom were farmers, came from six countries, primarily Germany and Poland. The lectures were published in November 1924; the first English translation appeared in 1928 as The Agriculture Course.

Steiner emphasized that the methods he proposed should be tested experimentally. For this purpose, Steiner established a research group, the "Agricultural Experimental Circle of Anthroposophical Farmers and Gardeners of the General Anthroposophical Society". This research group attracted, in the interval 1924 to 1939, about 800 members from around the world, including Europe, the Americas and Australasia. Another group, the "Association for Research in Anthroposophical Agriculture" (Versuchsring anthroposophischer Landwirte), directed by the German agronomist Erhard Bartsch, was formed to test the effects of biodynamic methods on the life and health of soil, plants and animals; the group published a monthly journal Demeter. Bartsch was also instrumental in developing a sales organisation for biodynamic products, Demeter, which still exists today. The Research Association was renamed The Imperial Association for Biodynamic Agriculture (Reichsverband für biologisch-dynamische Wirtschaftsweise) in 1933. It was dissolved by the National Socialist regime in 1941. In 1931 the association had 250 members in Germany, 109 in Switzerland, 104 in other European countries and 24 outside Europe. The oldest biodynamic farms are the Wurzerhof in Austria and Marienhöhe in Germany.

In 1938, Ehrenfried Pfeiffer's text Bio-Dynamic Farming and Gardening was published in five languages – English, Dutch, Italian, French, and German; this became the standard work in the field for several decades. In July 1939, at the invitation of Walter James, 4th Baron Northbourne, Pfeiffer travelled to the UK and presented the Betteshanger Summer School and Conference on Biodynamic Farming' at Northbourne's farm in Kent. The conference has been described as the 'missing link' between biodynamic agriculture and organic farming because, in the year after Betteshanger, Northbourne published his manifesto of organic farming, Look to the Land, in which he coined the term 'organic farming' and praised the methods of Rudolf Steiner. In the 1950s, Hans Mueller was encouraged by Steiner's work to create the organic-biological farming method in Switzerland; this later developed to become the largest certifier of organic products in Europe, Bioland.

Today biodynamics is practiced in more than 50 countries worldwide and in a variety of circumstances, ranging from temperate arable farming, viticulture in France, cotton production in Egypt, to silkworm breeding in China. Germany accounts for nearly half of the world's biodynamic agriculture. Demeter International is the primary certification agency for farms and gardens using the methods.

Geographic developments

• In Australia, the first biodynamic farmer was Ernesto Genoni who in 1928 joined the Experimental Circle of Anthroposophical Farmers and Gardeners, followed soon after by his brother Emilio Genoni. Bob Williams presented the first public lecture in Australia on biodynamic agriculture on 26 June 1938 at the home of the architects Walter Burley Griffin and Marion Mahony Griffin at Castlecrag, Sydney. Since the 1950s research work has continued at the Biodynamic Research Institute (BDRI) in Powelltown, near Melbourne under the direction of Alex Podolinsky. In 1989 Biodynamic Agriculture Australia was established, as a not for profit association.
• In 1928 the Anthroposophical Agricultural Foundation was founded in England; this is now called the Biodynamic Agriculture Association. In 1939, Britain's first biodynamic agriculture conference, the Betteshanger Summer School and Conference on Biodynamic Agriculture, was held at Lord Northbourne's farm in Kent; Ehrenfried Pfeiffer was the lead presenter.
• In the United States, the Biodynamic Farming & Gardening Association was founded in 1938 as a New York state corporation.
• In France the International Federation of Organic Agriculture Movements (IFOAM) was formed in 1972 with five founding members, one of which was the Swedish Biodynamic Association.
• The University of Kassel had a Department of Biodynamic Agriculture from 2006 to March 2011.

Biodynamic method of farming

In common with other forms of organic agriculture, biodynamic agriculture uses management practices that are intended to "restore, maintain and enhance ecological harmony." Central features include crop diversification, the avoidance of chemical soil treatments and off-farm inputs generally, decentralized production and distribution, and the consideration of celestial and terrestrial influences on biological organisms. The Demeter Association recommends that "(a) minimum of ten percent of the total farm acreage be set aside as a biodiversity preserve. That may include but is not limited to forests, wetlands, riparian corridors, and intentionally planted insectaries. Diversity in crop rotation and perennial planting is required: no annual crop can be planted in the same field for more than two years in succession. Bare tillage year round is prohibited so land needs to maintain adequate green cover."

The Demeter Association also recommends that the individual design of the land "by the farmer, as determined by site conditions, is one of the basic tenets of biodynamic agriculture. This principle emphasizes that humans have a responsibility for the development of their ecological and social environment which goes beyond economic aims and the principles of descriptive ecology." Crops, livestock, and farmer, and "the entire socioeconomic environment" form a unique interaction, which biodynamic farming tries to "actively shape ...through a variety of management practices. The prime objective is always to encourage healthy conditions for life": soil fertility, plant and animal health, and product quality. "The farmer seeks to enhance and support the forces of nature that lead to healthy crops, and rejects farm management practices that damage the environment, soil plant, animal or human health....the farm is conceived of as an organism, a self-contained entity with its own individuality," holistically conceived and self-sustaining. "Disease and insect control are addressed through botanical species diversity, predator habitat, balanced crop nutrition, and attention to light penetration and airflow. Weed control emphasizes prevention, including timing of planting, mulching, and identifying and avoiding the spread of invasive weed species."

Biodynamic agriculture differs from many forms of organic agriculture in its spiritual, mystical, and astrological orientation. It shares a spiritual focus, as well as its view toward improving humanity, with the "nature farming" movement in Japan. Important features include the use of livestock manures to sustain plant growth (recycling of nutrients), maintenance and improvement of soil quality, and the health and well being of crops and animals. Cover crops, green manures and crop rotations are used extensively and the farms to foster the diversity of plant and animal life, and to enhance the biological cycles and the biological activity of the soil.

Biodynamic farms often have a cultural component and encourage local community, both through developing local sales and through on-farm community building activities. Some biodynamic farms use the Community Supported Agriculture model, which has connections with social threefolding.

Compared to non-organic agriculture, BD farming practices have been found to be more resilient to environmental challenges, to foster a diverse biosphere, and to be more energy efficient, factors Eric Lichtfouse describes being of increasing importance in the face of climate change, energy scarcity and population growth.

Biodynamic preparations

In his "agricultural course" Steiner prescribed nine different preparations to aid fertilization, and described how these were to be prepared. Steiner believed that these preparations mediated terrestrial and cosmic forces into the soil. The prepared substances are numbered 500 through 508, where the first two are used for preparing fields, and seven are used for making compost. A long term trial (DOK experiment) evaluating the biodynamic farming system in comparison with organic and conventional farming systems, found that both organic farming and biodynamic farming resulted in enhanced soil properties, but had lower yields than conventional farming. Regarding compost development beyond accelerating the initial phase of composting, some positive effects have been noted:

• The field sprays contain substances that stimulate plant growth include cytokinins.
• Some improvement in nutrient content of compost.

Although the preparations have direct nutrient values, their purpose in biodynamics is to support the self-regulating capacities of the soil biota in the case of 500 and 501 and the biological life resident in the composting organics, as well as the mature compost itself, in the others.

Field preparations

Field preparations, for stimulating humus formation:

• 500: (horn-manure) a humus mixture prepared by filling the horn of a cow with cow manure and burying it in the ground (40–60 cm below the surface) in the autumn. It is left to decompose during the winter and recovered for use the following spring.
• 501: Crushed powdered quartz prepared by stuffing it into a horn of a cow and buried into the ground in spring and taken out in autumn. It can be mixed with 500 but usually prepared on its own (mixture of 1 tablespoon of quartz powder to 250 liters of water) The mixture is sprayed under very low pressure over the crop during the wet season, in an attempt to prevent fungal diseases. It should be sprayed on an overcast day or early in the morning to prevent burning of the leaves.

The application rate of the biodynamic field spray preparations (i.e., 500 and 501) are 300 grams per hectare of horn manure and 5 grams per hectare of horn silica. These are made by stirring the ingredients into 20-50 liters of water per hectare for an hour, using a prescribed method.

Compost preparations

Compost preparations, used for preparing compost, employ herbs which are frequently used in medicinal remedies. Many of the same herbs are used in organic practices to make foliar fertilizers, turned into the soil as green manure, or in composting. The preparations include:

• 502: Yarrow blossoms (Achillea millefolium) are stuffed into urinary bladders from Red Deer (Cervus elaphus), placed in the sun during summer, buried in earth during winter and retrieved in the spring.
• 503: Chamomile blossoms (Matricaria recutita) are stuffed into small intestines from cattle buried in humus-rich earth in the autumn and retrieved in the spring.
• 504: Stinging nettle (Urtica dioica) plants in full bloom are stuffed together underground surrounded on all sides by peat for a year.
• 505: Oak bark (Quercus robur) is chopped in small pieces, placed inside the skull of a domesticated animal, surrounded by peat and buried in earth in a place where lots of rain water runs past.
• 506: Dandelion flowers (Taraxacum officinale) are stuffed into the mesentery of a cow and buried in earth during winter and retrieved in the spring.
• 507: Valerian flowers (Valeriana officinalis) are extracted into water.
• 508: Horsetail (Equisetum).

The compost preparations are applied with quantities of 1–2 cm³ each per 10 m³ compost, farmyard manure or liquid manure. The preparations should then be evenly sprayed out on the land as soon as possible after stirring.

One to three grams (a teaspoon) of each preparation is added to a dung heap by digging 50 cm deep holes with a distance of 2 meters from each other, except for the 507 preparation, which is stirred into 5 liters of water and sprayed over the entire compost surface. All preparations are thus used in homeopathic quantities. Each compost preparation is designed to guide a particular decomposition process in the composting mass. One study found that the oak bark preparation improved disease resistance in zucchini.

Planting calendar

The approach considers that there are lunar and astrological influences on soil and plant development—for example, choosing to plant, cultivate or harvest various crops based on both the phase of the moon and the zodiacal constellation the moon is passing through, and also depending on whether the crop is the root, leaf, flower, or fruit of the plant. This aspect of biodynamics has been termed "astrological" in nature.

Seed production

Biodynamic agriculture has focused on the open pollination of seeds (with farmers thereby generally growing their own seed) and the development of locally adapted varieties. The seed stock is not controlled by large, multinational seed companies.

Biodynamic certification

The biodynamic certification Demeter, created in 1924 and named for the goddess of fertility, grain and agriculture, was the first certification and labelling system for organic production. This organization is a non-profit, international organization with certifying systems in 45 countries. To receive certification as a biodynamic farm, the farm must meet the following standards: agronomic guidelines, greenhouse management, structural components, livestock guidelines, and post harvest handling and processing procedures.

The term Biodynamic is a trademark held by the Demeter association of biodynamic farmers for the purpose of maintaining production standards used both in farming and processing foodstuffs.(This is not a trademark held privately in New Zealand) The trademark is intended to protect both the consumer and the producers of biodynamic produce. Demeter International an organization of member countries; each country has its own Demeter organization which is required to meet international production standards (but can also exceed them). The original Demeter organization was founded in 1928; the U.S. Demeter Association was formed in the 1980s and certified its first farm in 1982. In France, Biodivin certifies biodynamic wine. In Egypt, SEKEM has created the Egyptian Biodynamic Association (EBDA), an association that provides training for farmers to become certified. As of 2006, more than 200 wineries worldwide were certified as biodynamic; numerous other wineries employ biodynamic methods to a greater or lesser extent.

Similar to the Organic Certification, biodynamic farms certify through independent certifying agencies which interpret Demeter Farm Standards when certifying a farm. To transition to biodynamic, conventional farms must follow The Farm Standards for three years before being able to market their products as biodynamic, while certified organic farms only need to follow biodynamic standards for one. Demeter sees biodynamic farming as the paragon of sustainability as the emphasis is on the generation of inputs out of the living dynamics of the farm itself, rather than being imported from the outside.

Certified Demeter operations in member countries of
Demeter-International (DI), 2/2016
	ha	farms	processors	distributors
Austria	5.657	184	31	2
Brazil	2.833	51	16	14
Denmark	2.279	32	6	8
Egypt	2.438	133	2	6
Finland	400	18	5	6
France	9.873	439	31	38
Germany	72.588	1.476	368	56
Great Britain	4.309	96	38	9
Italy	11.524	388	50	30
Luxembourg	554	9	2	1
The Netherlands	5.948	134	74	21
New Zealand	1.003	23	5	1
Norway	532	22	9	3
Slovenia	141	34	1	1
Spain	4.465	75	10	3
Sweden	812	15	3	5
Switzerland	4.196	250	97	29
USA	4.195	107	54	24
total	133.747	3.486	802	257
Certified Demeter operations in other countries
	ha	farms	processors	distributors
Argentina	1.047	22	7	1
Belgium	57	9	8	3
Bulgaria	152	1	0	1
Canada	653	3	2	0
Chile	1.298	18	3	1
China	44	3	0	0
Costa Rica	11	1	0	1
Croatia	54	1	0	0
Czech Republic	5.722	6	0	1
Dominican Rep.	404	4	2	1
Ecuador	30	77	1	0
Eritrea	24	1	3	0
Ethiopia	28	1	0	0
Ghana	88	1	0	0
Greece	295	21	7	2
Guinea Bissao	73	1	0	0
Honduras	46	1	0	0
Hong Kong	0	0	0	1
Hungary	5.723	15	4	1
India	4.958	403	6	0
Ireland	23	3	0	0
Israel	85	2	1	0
Japan	0	0	0	3
Kuwait	0	0	0	1
Liechtenstein	0	0	1	0
Lithuania	518	7	0	0
Malaysia	0	0	0	1
Mexico	277	3	1	0
Morocco	120	1	0	0
Nepal	117	2	0	0
Paraguay	784	2	0	0
Peru	80	2	0	0
Poland	3.520	17	1	0
Portugal	382	6	1	0
Romania	145	1	0	0
Russian Federation	0	0	0	1
Sicily	583	22	2	0
Slowakia	161	1	1	0
South Africa	123	3	0	0
Sri Lanka	912	513	0	0
Tunisia	780	127	3	0
Turkey	1.143	168	2	0
Uganda	116	1	0	0
Ukrain	0	0	0	1
United Arab Emirates	0	0	0	1
Uruguay	0	0	1	0
total	30.576	1.470	49	21
alltogether	164.323	4.956	851	278

Effectiveness

Biodynamic farming only became the subject of research over the last few decades and research into biodynamic farming has been complicated by the difficulty of isolating the distinctively biodynamic aspects when conducting comparative trials. Consequently, there is no strong body of material that provides evidence of any specific effect. Nevertheless, there is a fair share of peer reviewed research results on controlled field experiments and case studies which show the effects of biodynamic preparations on soil quality, yield and biodiversity.

Similarly to Organic farming, Biodynamic methods display "less stressed soils and thus diverse and highly interrelated soil communities".

A 2009/2011 review found that biodynamically cultivated fields:

• had lower absolute yields than conventional farms, but achieved better efficiency of production relative to the amount of energy used;
• had greater earthworm populations and biomass than conventional farms.

Both factors were similar to the result in organically cultivated fields.

Further research on the biodynamic preparations have shown them to have positive effects on yields, on processes in compost piles and on soils in the field. Carpenter-Boggs et al. report higher average temperatures compared to control piles in active compost piles. They also found that compost treated with preparations had 65% more nitrate in final samples, respired CO2 was 10% lower and dehydrogenase enzyme activity to CO2 ratio was much higher. Microbial populations in these samples were found to be substantial in Biodynamic compost treated with preparations and “several bacterial and fungal strains showed a potential for suppressing fungal plant pathogens.” Though some in the scientific community maintain that preparations are used in too small amounts to make a difference, others claim that homeopathic remedies, herbidices and pesticides are often used in small amounts, yet they are able to bring forth multiplied effects. Turinek and his team encourage further research “designed to separate the effects of the preparations from other aspects of the BD farming method.”

The effects of organic and biodynamic systems are difficult to separate in terms of biodiversity, though Fließbach et al. reported less dense but more diverse weed species in biodynamic plots as compared to organic plots. Biodynamic and Organic treatments have also been found to affect earthworm species composition and quantity. Additionally, biodynamic methods have been found to affect microflora in soils. Another study discovered that farmyard manure applications adds to the stability of soil biological functions between microbial bacteria and fungal populations.

Reception

In a 2002 newspaper editorial, Peter Treue, agricultural researcher at the University of Kiel, characterized biodynamics as pseudoscience and argued that similar or equal results can be obtained using standard organic farming principles. He wrote that some biodynamic preparations more resemble alchemy or magic akin to geomancy.

In a 1994 analysis, Holger Kirchmann, a soil researcher with the Swedish University of Agricultural Sciences, concluded that Steiner's instructions were occult and dogmatic, and cannot contribute to the development of alternative or sustainable agriculture. According to Kirchmann, many of Steiner's statements are not provable because scientifically clear hypotheses cannot be made from his descriptions. Kirchmann asserted that when methods of biodynamic agriculture were tested scientifically, the results were unconvincing. Further, in a 2004 overview of biodynamic agriculture, Linda Chalker-Scott, a researcher at Washington State University, characterized biodynamics as pseudoscience, writing that Steiner did not use scientific methods to formulate his theory of biodynamics, and that the later addition of valid organic farming techniques has "muddled the discussion" of Steiner's original idea. Based on the scant scientific testing of biodynamics, Chalker-Scott concluded "no evidence exists" that homeopathic preparations improve the soil.

In Michael Shermer's The Skeptic Encyclopedia of Pseudoscience, Dan Dugan says that the way biodynamic preparations are supposed to be implemented are formulated solely on the basis of Steiner's "own insight". Skeptic Brian Dunning writes "the best way to think of 'biodynamic agriculture' would be as a magic spell cast over an entire farm. Biodynamics sees an entire farm as a single organism, with something that they call a life force."

Florian Leiber, Nikolai Fuchs and Hartmut Spieß, researchers at the Goetheanum, have defended the principles of biodynamics and suggested that critiques of biodynamic agriculture which deny it scientific credibility are "not in keeping with the facts...as they take no notice of large areas of biodynamic management and research." Biodynamic farmers are "charged with developing a continuous dialogue between biodynamic science and the natural sciences sensu stricto," despite important differences in paradigms, world views, and value systems.

Philosopher of science Michael Ruse has written that followers of biodynamic agriculture rather enjoy the scientific marginalisation that comes from its pseudoscientific basis, revelling both in its esoteric aspects and the impression that they were in the vanguard of the wider anti-science sentiment that has grown in opposition to modern methods such as genetic modification.

See also

• Agroecology
• Alan Chadwick
• Biointensive agriculture
• Ehrenfried Pfeiffer
• List of topics characterized as pseudoscience
• Permaculture
• The Real Dirt on Farmer John - documentary on a conventional farm which converted to biodynamic and community-supported agriculture
• Wild farming

Further reading

Biodynamic Agricultural Association (n.d.). "How does the Calendar work?". Biodynamic Frequently Asked Questions. The Biodynamic Agricultural Association (UK). Archived from the original on 2007-09-28. Retrieved 2007-10-05.{{cite web}}: CS1 maint: year (link)

Burkitt, L.L.; D R. Small; J.W. McDonald; W.J. Wales; M.L. Jenkin (2007a). "Comparing irrigated biodynamic and conventionally managed dairy farms. 1. Soil and pasture properties". Australian Journal of Experimental Agriculture. 47 (5). Melbourne, Australia: Commonwealth Scientific and Industrial Research Organisation Publishing: 479–488. doi:10.1071/EA05196. OCLC 12490171.

Burkitt, L.L.; W.J. Wales; J.W. McDonald; D R. Small; M.L. Jenkin (2007b). "Comparing irrigated biodynamic and conventionally managed dairy farms. 2. Milk production and composition and animal health". Australian Journal of Experimental Agriculture. 47 (5). Melbourne, Australia: Commonwealth Scientific and Industrial Research Organisation Publishing: 489–494. doi:10.1071/EA06085. OCLC 12490171.

Chalker-Scott, Linda (2004). "The Myth of Biodynamic Agriculture" (PDF). Horticultural Myths. Washington State University Puyallup Research & Extension Center. Retrieved 2007-10-05.

Diver, Steve (1999). "Biodynamic Farming & Compost Preparation (ATTRA Publication #IP137)". ATTRA - National Sustainable Agriculture Information Service. Retrieved 2007-10-05.

Harwood, Richard R. (1990). "A History of Sustainable Agriculture". In Clive A. Edwards, Rattan Lal, Patrick Madden, Robert H. Miller and Gar House (Eds.) (ed.). Sustainable Agricultural Systems. Ankeny, IA: Soil and Water Conservation Society. pp. 3–19. ISBN 0-935734-21-X. OCLC 20933949.{{cite book}}: CS1 maint: multiple names: editors list (link)

Koepf, Herbert (2009). Research in Biodynamic Agriculture: Methods and Results. Biodynamic Farm and Gardening Association. ISBN 0-938250-34-5.

Kristiansen, Paul (2006). "Overview of organic agriculture" (PDF). In Paul Kristiansen, Acram Taji and John Reganold (ed.). Organic Agriculture: A Global Perspective (online sample reprint ed.). Collingwood, VIC: CSIRO Publishing. pp. 1–23. ISBN 978-0-643-09090-3. OCLC 71801183. {{cite book}}: |chapter-format= requires |chapter-url= (help); External link in |chapterurl= (help); Unknown parameter |chapterurl= ignored (|chapter-url= suggested) (help)

Mäder, Paul; Andreas Fließbach; David Dubois; Lucie Gunst; Padruot Fried; Urs Niggli (2002). "Soil fertility and biodiversity in organic farming". Science. 296 (5573). New York, NY: American Association for the Advancement of Science: 1694–1697. doi:10.1126/science.1071148. OCLC 1644869. PMID 12040197. Archived from the original (Summary) on October 25, 2007. Retrieved 2007-10-11. {{cite journal}}: Unknown parameter |deadurl= ignored (|url-status= suggested) (help)

Martinez, A.W. (1952-05-31). "The City With Golden Garbage" (Reprint). Collier's Weekly. Springfield, OH: Crowell-Collier. OCLC 8755061. Retrieved 2007-10-05.

Nastati, Enzo (2010). "Commentary on Dr Rudolf Steiner's Agriculture Course". MM Publications.

Pfeiffer, Ehrenfried (2006) [1938]. Soil Fertility, Renewal and Preservation: Bio-Dynamic Farming and Gardening. Delhi, India: Asiatic Publishing House. ISBN 81-87067-73-X.

Schilthuis, Willy (2003). Biodynamic Agriculture. Floris Books. ISBN 0-86315-397-6.

References

Bibliography

• Proctor, Peter (1997). Grasp the Nettle: Making Biodynamic Farming & Gardening Work. With Gillian Cole. Random House. {{cite book}}: Invalid |ref=harv (help)

External links

• Biodynamics Section at the Rudolf Steiner Archive, An Online Library