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</o:shapelayout></xml><![endif]--></head><body bgcolor=white lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Charcoal burns in direct contact with air well above 600 C so any fire at the charcoal stage would be above 500-600C. Higher temperature oxidized chars have great adsorption properties. They compost readily. Great way to make terra preta. <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Tom<o:p></o:p></span></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> biochar-policy@yahoogroups.com [mailto:biochar-policy@yahoogroups.com] <b>On Behalf Of </b>Kevin<br><b>Sent:</b> Tuesday, December 11, 2012 8:18 PM<br><b>To:</b> rongretlarson@comcast.net; Discussion of biomass cooking stoves; biochar-policy<br><b>Cc:</b> Alex English; Tom Miles<br><b>Subject:</b> [biochar-policy] Re: [Stoves] Equipment required for testing stoves<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal> <o:p></o:p></p><div id=ygrp-mlmsg><div id=ygrp-msg><div id=ygrp-text><p> <o:p></o:p></p><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif"'>Dear Ron</span><o:p></o:p></p></div><blockquote style='border:none;border-left:solid black 1.5pt;padding:0in 0in 0in 0in;margin-top:5.0pt;margin-bottom:5.0pt'><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>----- Original Message ----- <o:p></o:p></span></p></div><div><p class=MsoNormal style='background:#E4E4E4'><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'> <a href="mailto:rongretlarson@comcast.net" title="rongretlarson@comcast.net">rongretlarson@comcast.net</a> <o:p></o:p></span></p></div><div><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>To:</span></b><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'> <a href="mailto:stoves@lists.bioenergylists.org" title="stoves@lists.bioenergylists.org">Discussion of biomass cooking stoves</a> ; <a href="mailto:biochar-policy@yahoogroups.com" title="biochar-policy@yahoogroups.com">biochar-policy</a> <o:p></o:p></span></p></div><div><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Cc:</span></b><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'> <a href="mailto:english@kingston.net" title="english@kingston.net">Alex English</a> ; <a href="mailto:kchisholm@ca.inter.net" title="kchisholm@ca.inter.net">Kevin Chisholm</a> ; <a href="mailto:tmiles@trmiles.com" title="tmiles@trmiles.com">Tom Miles</a> <o:p></o:p></span></p></div><div><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Sent:</span></b><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'> Tuesday, December 11, 2012 2:09 AM<o:p></o:p></span></p></div><div><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Subject:</span></b><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'> Re: [Stoves] Equipment required for testing stoves<o:p></o:p></span></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'>Lists (adding biochar-policy also), Kevin, Alex, Tom (who I add, because he speaks Portuguese and might have caught an answer when we were in Manaus a few years ago)<br><br> See below<o:p></o:p></span></p><div class=MsoNormal align=center style='text-align:center'><span style='font-family:"Arial","sans-serif";color:black'><hr size=3 width="100%" align=center id=zwchr></span></div><p class=MsoNormal><b><span style='font-family:"Arial","sans-serif";color:black'>From: </span></b><span style='font-family:"Arial","sans-serif";color:black'>"Kevin" <<a href="mailto:kchisholm@ca.inter.net">kchisholm@ca.inter.net</a>><br><b>To: </b>"Discussion of biomass cooking stoves" <<a href="mailto:stoves@lists.bioenergylists.org">stoves@lists.bioenergylists.org</a>>, "Alex English" <<a href="mailto:english@kingston.net">english@kingston.net</a>><br><b>Cc: </b>"Discussion of biomass cooking stoves" <<a href="mailto:stoves@lists.bioenergylists.org">stoves@lists.bioenergylists.org</a>><br><b>Sent: </b>Monday, December 10, 2012 8:24:34 PM<br><b>Subject: </b>Re: [Stoves] Equipment required for testing stoves<br><br> <o:p></o:p></span></p><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'>Dear Ron<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'>Would you agree that the Amazonians made Terra Preta with low temperature char? <br> <b>[RWL1: I think others may have an answer - maybe based on spectroscopy. I will start looking but don't know that field well enough to know what others may have concluded about these ancient soils. I fear that 500 years (minimum) in soil may hide the initial character that we can readily see in a University setting. I know from being in several Amazonian biochar "pits" that it is pretty hard to find a piece big enough to test. I think it entirely possible that char left over from simple three-stone fires could have been made at 500-600 C (or higher). Would you call those temperatures high or low?] </b><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'> <o:p></o:p></span></p></div><div><p class=MsoNormal><b><span style='font-family:"Arial","sans-serif";color:black'># KC1: Obviously, I am speculating, but I would speculate that Terra Preta was made with charcoal from a number of sources:</span></b><span style='font-family:"Arial","sans-serif";color:black'><o:p></o:p></span></p></div><div><p class=MsoNormal><strong><span style='font-family:"Arial","sans-serif";color:black'>1: Char residue remaining after charring or burning of "wood waste from initial jungle clearing.</span></strong><span style='font-family:"Arial","sans-serif";color:black'><o:p></o:p></span></p></div><div><p class=MsoNormal><strong><span style='font-family:"Arial","sans-serif";color:black'>2: Char residue remaining from charring or burning of agricultural waste and weeds</span></strong><span style='font-family:"Arial","sans-serif";color:black'><o:p></o:p></span></p></div><div><p class=MsoNormal><strong><span style='font-family:"Arial","sans-serif";color:black'>3: Char and ash residue from cooking fires and possibly smudge pots</span></strong><span style='font-family:"Arial","sans-serif";color:black'><o:p></o:p></span></p></div><div><p class=MsoNormal><strong><span style='font-family:"Arial","sans-serif";color:black'>4: Organic fertilizer supplements, from humanure, composted food scraps, and probably dredgings from oxbow lakes.</span></strong><span style='font-family:"Arial","sans-serif";color:black'><o:p></o:p></span></p></div><div><p class=MsoNormal><strong><span style='font-family:"Arial","sans-serif";color:black'>I would consider 500-600 C to be a "low temperature char." I haven't seen any references to the existence of bellows technology in ancient Amazonia, that would be necessary to produce significantly higher temperatures.</span></strong><span style='font-family:"Arial","sans-serif";color:black'><o:p></o:p></span></p></div><div><p class=MsoNormal><strong><span style='font-family:"Arial","sans-serif";color:black'>It is likely that the Amazonian Terrapretians would have quickly noticed if such low temperature char additions to their agricultural practises were causing poor results. If that was the case, they likely would have taken steps to avoid application of char to fields. They would be looking for short term benefits or harm. Given that they used char on a widespread basis, and that it was basically low temperature char, it would thus seem that Terra Preta worked with low temperature char, and it worked relatively quickly, not requiring an aging period of several years.</span></strong><span style='font-family:"Arial","sans-serif";color:black'><o:p></o:p></span></p></div></div></blockquote><blockquote style='border:none;border-left:solid black 1.5pt;padding:0in 0in 0in 0in;margin-top:5.0pt;margin-bottom:5.0pt'><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'><br><br><br>If so, are there any test results to show that an "intermediate temperature char" would give better results than the "low temperature char?"<br> <b>[RWL2: I think that people like Dr. Johannes Lehmann and Evelyn Krull may be getting to an answer for some specific soil and species. I keep looking for it.<br> My note below to Alex was to make it easier for users to know what is being used Some of my favorite biochar scientists like Drs. Julie Major and Christoph Steiner were forced to use char bought off the side of a remote Amazonian road. <br> I haven't seen any data emphasizing tests with a range of temperatures. Drs. Stephen Joseph (low) and Hugh McLaughlin (high) recommend different temperature regimes.] </b><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'> <o:p></o:p></span></p></div><div><p class=MsoNormal><b><span style='font-family:"Arial","sans-serif";color:black'>#KC2: Is it perhaps likely that "basic low temperature biochar" is good for general agricultural applications, but that intermediate and high temperature chars may be better for addressing special agricultural problems. </span></b><span style='font-family:"Arial","sans-serif";color:black'><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'>I seem to recall that "high temperature char" and/or "activated char" gives inferior results in a biochar application. <br> <b>[RWL3: How about giving a cite for that?] </b><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'> <o:p></o:p></span></p></div><div><p class=MsoNormal><b><span style='font-family:"Arial","sans-serif";color:black'>#KC3: Unfortunately, I cannot point to a specific cite.</span></b><span style='font-family:"Arial","sans-serif";color:black'><br><br>Does this impression make sense to you? <br> <b>[RWL4: No - certainly not as a universal truth/] </b><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'> <o:p></o:p></span></p></div><div><p class=MsoNormal><b><span style='font-family:"Arial","sans-serif";color:black'>#KC4: Universal truths are scarce and hard to find. :-) If you put yourself in the circumstances of an Amazonian Terrapretian of 3,000 years ago, what would you do differently?</span></b><span style='font-family:"Arial","sans-serif";color:black'><br><br>If so, is there a "preferred char making temperature range"? <br> <b>[RWL5: I am sure that it depends a lot on the intended recipient soil - and probably on the plant species. #KC5:1 Certainly! Jungle woods can vary in density from balsa at about 10 lb/cubic foot, to Lignum Vitae, at about 68 pounds per cubic foot.</b><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'> <o:p></o:p></span></p></div><div><p class=MsoNormal><b><span style='font-family:"Arial","sans-serif";color:black'>My focus in this exchange below with Alex is to give soil researchers and stove users a better idea of even getting close to knowing what char-T they are using. </span></b><span style='font-family:"Arial","sans-serif";color:black'><o:p></o:p></span></p></div><div><p class=MsoNormal><b><span style='font-family:"Arial","sans-serif";color:black'>#KC5:2 Char making temperature is easy to determine. It should thus be very easy to determine the importance, or lack thereof, of char making temperature. It would be very good to know this, to reduce variables in a test analysis.</span></b><span style='font-family:"Arial","sans-serif";color:black'><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'> <o:p></o:p></span></p></div><div><p class=MsoNormal><b><span style='font-family:"Arial","sans-serif";color:black'> There is a good bit of information out there relating pH to production temperature - but pH also depends on fuel size and ash content and pH changes over time. Who knows what else leads to a "preference"? <br> And we also hear from Dr. Spokas that what happens after char production is maybe as much or more important. I think it is absolutely amazing that we hear so many good reports (and few bad reports) when we know so little even about the char-production temperature - and even the wood species, etc, etc, etc. Ron] </span></b><span style='font-family:"Arial","sans-serif";color:black'><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'> <o:p></o:p></span></p></div><div><p class=MsoNormal><b><span style='font-family:"Arial","sans-serif";color:black'>#KC: With that many "good reports" and so few "bad reports", and with so many char variables, this would tend to downplay the importance of char variables. The "bad reports", presuming that they were competently done, could provide very important insights into what works, and what doesn't.</span></b><span style='font-family:"Arial","sans-serif";color:black'><o:p></o:p></span></p></div></blockquote><blockquote style='border:none;border-left:solid black 1.5pt;padding:0in 0in 0in 0in;margin-top:5.0pt;margin-bottom:5.0pt'><div><p class=MsoNormal><span style='font-size:13.5pt;font-family:"Arial","sans-serif";color:black'>Best wishes,</span><span style='font-family:"Arial","sans-serif";color:black'><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:13.5pt;font-family:"Arial","sans-serif";color:black'>Kevin</span><span style='font-family:"Arial","sans-serif";color:black'><o:p></o:p></span></p></div></blockquote><blockquote style='border:none;border-left:solid black 1.5pt;padding:0in 0in 0in 0in;margin-top:5.0pt;margin-bottom:5.0pt'><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'>Best wishes,<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'>Kevin<o:p></o:p></span></p></div><blockquote style='border:none;border-left:solid black 1.5pt;padding:0in 0in 0in 0in;margin-top:5.0pt;margin-bottom:5.0pt'><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'>----- Original Message ----- <o:p></o:p></span></p></div><div><p class=MsoNormal style='background:#E4E4E4'><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'>From:</span></b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'> <a href="mailto:rongretlarson@comcast.net" target="_blank" title="rongretlarson@comcast.net">rongretlarson@comcast.net</a> <o:p></o:p></span></p></div><div><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'>To:</span></b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'> <a href="mailto:english@kingston.net" target="_blank" title="english@kingston.net">Alex English</a> <o:p></o:p></span></p></div><div><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'>Cc:</span></b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'> <a href="mailto:stoves@lists.bioenergylists.org" target="_blank" title="stoves@lists.bioenergylists.org">Discussion of biomass cooking stoves</a> <o:p></o:p></span></p></div><div><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'>Sent:</span></b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'> Monday, December 10, 2012 9:46 PM<o:p></o:p></span></p></div><div><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'>Subject:</span></b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'> Re: [Stoves] Equipment required for testing stoves<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'><o:p> </o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'><span style='font-family:"Arial","sans-serif";color:black'>Alex:<br><br> Thanks:<br><br> I see only a few remaining questions related to the thermocouples. My interest is only in being able to report to the soil scientists the temperature at which the char was produced.<br><br> Q1. I think we should be able to say that a time average of a central thermocouple measurement showing a slight drop over time of the highest numbers is a pretty good estimate - that could be reproduced for "any" similar "flaming pyrolysis" approacd. The properties (pH, surface areas, labile component, etc) of such char should be compared (a Master's thesis?) with char produced via other means. I think Nat Mulcahy's non-flaming pyrolysis approach can produce varying temperature char. An all-electric heating approach in any oxygen-free environment , operated at different temperature should also be used to compare the char properties with those from stoves. Maybe that data is already out there?? <br><br> Q2. I think there could be some influence of the initial fuel moisture content. Do you (anyone) have an opinion on that? I am trying to avoid having to always measure temperatures, but still be able to give an indication of the "likely" char temperature, by knowing how long a specific volume or weight of fuel lasted.<br><br> Q3. I wonder if the char temperature as measured by a thermocouple system like yours would also be a function of the fuel itself (species, characteristic size, shape, etc.)<br><br> Q4. I am pretty sure that the top and bottom char will be significantly different in a typical cooking cycle, where a very high flame temperature is desired at first (affecting only the top part of the fuel load), and then a much lower temperature desired later (affecting only the lowest portion of the fuel load). My question, for anyone, is whether an average temperature is at all valuable, if the average (obtained from the total duration of the pyrolysis) covered a wide range of production temperatures. Actually I have heard so many different opinions on the best production temperature - maybe a mixture of char temperatures might be an advantage. Thoughts?<br><br><br>Ron<br><br><o:p></o:p></span></p><div class=MsoNormal align=center style='text-align:center'><span style='font-family:"Arial","sans-serif";color:black'><hr size=3 width="100%" align=center id=zwchr></span></div><p class=MsoNormal style='margin-bottom:12.0pt'><b><span style='font-family:"Arial","sans-serif";color:black'>From: </span></b><span style='font-family:"Arial","sans-serif";color:black'>"Alex English" <<a href="mailto:english@kingston.net">english@kingston.net</a>><br><b>To: </b><a href="mailto:rongretlarson@comcast.net">rongretlarson@comcast.net</a>, "Discussion of biomass cooking stoves" <<a href="mailto:stoves@lists.bioenergylists.org">stoves@lists.bioenergylists.org</a>><br><b>Sent: </b>Monday, December 10, 2012 4:38:56 AM<br><b>Subject: </b>Re: [Stoves] Equipment required for testing stoves<o:p></o:p></span></p><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'>Ron,<br><br>On 09/12/2012 8:33 PM, <a href="mailto:rongretlarson@comcast.net" target="_blank">rongretlarson@comcast.net</a> wrote:<o:p></o:p></span></p></div><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><div><p class=MsoNormal style='margin-bottom:12.0pt'><span style='font-family:"Arial","sans-serif";color:black'>Alex etal<br><br> Thanks for the cite. I think I understand most of the plot - which was of amazing duration!. I am especially amazed at how uniform (and high) the flame temperature was in the late time plot, even as the other plots were dropping.<o:p></o:p></span></p></div></blockquote><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'>It is a very steady gas producer. Conditions are constant except for the distance and path composition between the pyrolysis front and the burner. If it can be done over 100cm then why not 200 or 300.<br><br><o:p></o:p></span></p><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'> a. Since you have this one from 2000, you probably have quite a few more - from which I/we might extract a good bit more information/ Any other similar plots around that you can post?<o:p></o:p></span></p></div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'>No I don't.<br><br><o:p></o:p></span></p><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'><br> b. I am surprised that the "pyrolysis gas temperature" was so much lower than the temperature of the char. Where was the probe for this measurement - and had there been some mixing of secondary air at this point?<o:p></o:p></span></p></div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'>No mixing of secondary air at that point. That occurs in and above in a 5cm burner mixing pipe. The tmperature difference is largely due to the nature of unshielded thermocouples in gas.For the most part thermocouples radiate away heat according to the temperatures of the surfaces that make up the sphere around them. A thermocouple buried in the pellets that are all carbonizing at 700C will give a fairly accurate measurement. A thermocouple in the gas above the top of the pellet bed will radiate to the pellet bed and, in this case the uninsulated container walls. The more that pellet bed shrinks the larger the portion of the radiant sphere that is the cool container walls. The larger the thermocouple, the greater the radiant cooling , the lower the measurement. The higher the temperature the greater the radiant loss, to the forth power. All the gas is also radiating and convecting heat to the container walls. So there are two reasons for a slow drop in gas temperature, and one reason for not trusting either. The same holds true for the absolute value of post combustion measurement. <br><br>There are </span><span style='font-family:"Arial","sans-serif";color:#222222;background:white'>gas-</span><em><span style='font-family:"Arial","sans-serif";color:black;background:white;font-style:normal'>aspirated pyrometers which shield a thermocouple with ceramic layers that approach gas temperatures and give better numbers. We will soon be using an 10 footer to probe the chain grate stoker gasses in carbonizer- pyrolysis-gasifier mode.</span></em><span style='font-family:"Arial","sans-serif";color:black;background:white'><br><br><em><span style='font-family:"Arial","sans-serif";font-style:normal'>Grate fun.</span></em><br><br></span><span style='font-family:"Arial","sans-serif";color:black'><o:p></o:p></span></p><div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'><br> c. What is the present disposition of this equipment?<o:p></o:p></span></p></div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'>Its in the recoverable bone yard. I should have shown it to Crispin when he was here.....or perhaps not:) <br><br>Alex<br><br><o:p></o:p></span></p><div><p class=MsoNormal style='margin-bottom:12.0pt'><span style='font-family:"Arial","sans-serif";color:black'><br>Nice work<br><br>Ron<br><br><o:p></o:p></span></p></div><p class=MsoNormal><span style='font-family:"Arial","sans-serif";color:black'><o:p> </o:p></span></p></div><div class=MsoNormal align=center style='text-align:center'><span style='font-family:"Arial","sans-serif";color:black'><hr size=3 width="100%" align=center></span></div><p class=MsoNormal style='margin-bottom:12.0pt'><span style='font-family:"Arial","sans-serif";color:black'>_______________________________________________<br>Stoves mailing list<br><br>to Send a Message to the list, use the email address<br><a href="mailto:stoves@lists.bioenergylists.org">stoves@lists.bioenergylists.org</a><br><br>to UNSUBSCRIBE or Change your List Settings use the web page<br><a 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