Laboratory Work in the Winter

This winter, Portland State University graduate student Emily Taber is running our avocational archaeology laboratory. Our dedicated volunteers-in-park archaeologists are working with Emily, Portland State University Research Assistant Katie Wynia and myself in preparing collections, analyzing, and interpreting the results. This year is special as we are preparing a synthetic report for the multi-year project in the Village. We also have three Washington State University Vancouver and one Portland State University interns helping out. Two are working on the flagstaff project from the summer and they have built a small exhibit in the fur store archaeology corridor inside the reconstructed fort. After about a month of laboratory work, everything is running smoothly and we are getting a handle on the multi-year project.

Notes from Jodi: In Lab and Field

This week I was assigned to lab. I was able to see what had come in from Block L and survey which was interesting because when I am up at the flag staff I have no contact with the rest of the group until the end of the day. As expected, there were many small sherds of many different types of ceramics to process because the week before block L had reached the house floor. There were also a lot of square nails, broken glass, broken clay pipe pieces, and many different types of artifacts to clean too.

On the first day we had a group of kids visiting from the Chehalis Tribe. There were about 35 kids and 6 adults. They were really interested in how we clean and process each different kind of artifact and they really seemed to enjoy viewing the many different artifacts we had out on the table at the time. 

I was also able to process my own finds from the flag staff and that was pretty nice to be able to see the artifacts come from the ground covered in soil to cleaning them up and getting them ready for processing. They look very different when all of the soil has been removed. I was even able to clean the wood that we recovered. We had to lightly brush the wood so that we wouldn’t destroy it. I think it’s pretty amazing to find wood in such great condition after being buried for over 125 years! It almost looked brand new!

After 2 days of lab, we were moved out to Block L because there wasn’t that much left to process in the lab. I began to work on unit L31 and was able to uncover over 40 sherds of ceramics and at least 20 pieces of glass. I also began to uncover a large triangular shaped piece of metal but I had to leave it in situ because it is still protruding out of the next level. I can’t wait to see what it may be!

In the unit next to me is where all of the action seemed to be. Heidi was working in that unit and uncovered a very large iron key! 

She also uncovered a large molar tooth that turned out to be pig's tooth. There were also many other large animal bones and post holes uncovered in Block L. In other news, I heard that at the Flag Staff dig they have reached 120 cm down and still have not reached the bottom of the pit that was dug to hold it. I wonder if they will uncover the flag staff this week? This is very exciting!

A Student's View of the Flag Staff Dig

Jodi Marshall: This week I was back at the Parade Ground in search of the elusive flag staff erected about 1850 after the U.S. military took over the fort. It was said to be so tall that it could be seen up and down the Columbia and might have been as tall as 150 feet! It disappeared from pictures and writtenrecords in the mid 1870s. As far as we know, it was not documented as to what happened to it so it is a mystery. We are also not sure as to how it was erected so we only have the knowledge of how it would have been traditionally done. What we are looking for is the base or ballast of the flag staff. The park would eventually like to reconstruct it along with the original path that lead from the front of the Grant house ( now a restaurant on the City of Vancouver's Officers Row) directly to the flag post. This is very exciting!

On the first day back at the site, I was brought up to speed as to what had happened while I was gone. There were four small holes or voids that had opened up within three of the four units. This was exciting at first but they ended up being Krotovina (rodent holes.) Bits of wood had became more abundant along with fire-cracked rock.

On the second day Dr. Beth Horton decided to bring one of our 1x1 meter units down farther than the rest as she was suspecting that it was near the flag staff. I screened all day and began to recover lithic debitage, which are stone flakes or biproducts from making stone tools. This was very puzzling because the level that we were in was the age of the US military and not of a precontact American Indian site. So how did the debitage get in there? We are still not sure. There were also many new holes that opened up within the unit but looked like they were Krotovina again or perhaps just loose dirt from the flagstaff hole.

On day three Beth uncovered a very large piece of wood in the middle of one of the Units. The next day it was uncovered even more and turned out to be a larger piece of timber sitting at about a 45 degree angle. There was also a larger piece of timber discovered sitting on the western side of the same unit. There are still many pieces of lithic debitage being recovered in this unit too. The south east corner began to collapse or crumble down as if there were a large void underneath it. It turns out that it was just loose soil due to having been disturbed some time ago. Could this mean we have found the site of the flag staff? Stay tuned…      

Editors note: a story in the Columbian just ran on the flag staff dig. Here is the link: http://www.columbian.com/news/2014/jul/23/students-dig-in-at-fort-flagpole-site/

A Student's View of Archaeological Survey

I had the opportunity to be on the survey team this week. Earlier in the week we learned how to measure our own personal pace unit. My magic number is .701cm per each step I take. We also learned to walk in transects as a group and using a compass. It was much harder than I thought it would be due to the hills and uneven terrain we were practicing in. Who knew walking a straight line could be so hard! When we first did it, we were directly outside of the fort in the field and Heidi happened upon a hatchet left after a demonstration probably for the Fourth of July. Later on I found a woman’s bracelet up on the upper parade ground and turned it in.

We spent a few days digging 40cm wide by 80cm deep test probes in the area of the old Spruce Mill site to help locate the tent city that was within the mill area. In all we dug 12 holes. We mostly found a lot of asphalt and concrete left over from the old hangers but we also found some broken glass, a few machine cut nails, fire-cracked rock, small pieces of brick, a small metal hook, and even an old cigarette butt. It was very hot during the week and there was little shade to enjoy throughout the day. It is in a large field however and there was an abundance of birds to watch. I even found a wasp’s nest within the tall grass. We had just a few visitors this week, surprisingly mostly people that had a lot of knowledge about the site or archeology itself.

Today we finished up the week learning how to read and create maps by utilizing a compass and GPS. Our team leader Justin created two different “sites” and we had to map them out using both methods. One was an old cabin with a “fallen plank,” a tin can, a piece of broken glass, and a shot gun shell so we hypothesized that the depositshappened by someone sitting on a porch, eating out of a can of beans, and shooting their gun. The second “site” was of a precontact site due to the absence of any European or post contact material. There was a projectile point, a ring of cobbles as if there were arranged for a fire, flint knapping debris, and animal bone. I really enjoyed this exercise. Next week I will be working again at the flag staff. I heard that they might be getting close to uncovering the post. How exciting!

Another student blog post

From Last Week:

Jodi Marshall: Today I was happy to find out that I would be working up at the flag staff this week. Last week I heard that they were beginning to find things like nails and glass. I too found similar things today. It seems peculiar that there is any kind of debris at this site where the flag staff is thought to have stood. Given all of the shards of glass and fire-cracked rock, I feel that we have some sort of dump site that was burned. I am pondering this however because I can’t understand yet why the military would have thrown any kind of rubbish on the parade grounds.

Students excavate at the Vancouver Barracks Parade Ground. The hole you see in this photo is a void that may be related to the site of the post's Flag Staff. Hopefully our excavations this summer will let us know for sure!

The parade ground itself was quite busy today as the Fourth of July is almost upon us. The Army was there practicing for a change-of-command ceremony. A few soldiers came over to inquire what we were doing. We also had a group of young people come over to watch us.  One of the girls asked how we found the area where we think the flag staff is located and Mikayla and I had a chance to explain to the group that we had used a magnetometer to help locate it. They were also excited to be able to watch Heidi screen a bucket of excavated sediment. This site is so interesting and I can’t wait to reach the next stratum. 

Blogging about Fort Vancouver, a Student's View

As part of an internship in public archaeology, some of our students will be periodically posting about their experiences at the Fort Vancouver Public Archaeology Field School. This will provide a different perspective on the school that will augment my posts.  Enjoy!

Jodi Marshall: I have been working on Block L (the Little Prouxl House Site) for the last few days and have found it challenging but very interesting. When we first uncovered the fill from the block that had been placed in it last year, you could clearly see the different levels of strata along the exposed walls. Doug Wilson mapped out eight new units to excavate west and south of the block.

So far we have found a piece of flat glass, bits of charcoal, and a few wire cut nails. In the unit across from ours a piece of transferprinted whiteware was discovered. There have been many pieces of expended copper bullets (they called it shrapnel two years ago until they figured out they were bullets, probably shot at a target) found within my unit. Overall, it has been interesting peeling back the layers from different time periods and I am very excited to see what lies beneath.

This field photo of a piece of transferprinted ceramic whiteware was found in 20th century deposits above the World War I railroad spur line. It is an out-of-context artifact that suggests that earlier fur-trade and early U.S. Army deposits are nearby.

The weather overall has been good. There have only been just a small handful of people coming and visiting the dig site but I am sure this will increase as the summer progresses. We have been touring the fort as well and have been learning many interesting facts about not only the structures but the people that lived here as well. I was surprised to learn that General Ulysses Grant never actually lived at the Grant House (named in his honor after he had finished his presidency). It is also interesting that there were so many other buildings at the fort that were reconstructed based on archaeology.  I am excited to start the excavation on the parade grounds at what we think is where the old flag staff was. Since there are no up close pictures of it, we are relying on old images of the landscape that include the flag staff. By looking at the pictures, it was very tall and could probably have been seen for many miles up and down the Columbia River. It must have been quite an impressive sight to behold as people traveled by.   

Return to Fort Vancouver

Exploring Fort Vancouver National Historic Site: The Public Archaeology Field School at Fort Vancouver National Historic Site

Tuesday - Saturday, June 17 - August 2, 2014

Well, it is time for the archaeologists to return to the Village and elsewhere at Fort Vancouver. This summer, Portland State University, Washington State University Vancouver, and the National Park Service will be conducting its 13th  field school in historical archaeology at Fort Vancouver National Historic Site. Students in the field school will work with Park Service archaeologists to conduct archaeological excavations throughout the park.

Students will be primarily working in two areas. Teams of student archaeologists will be returning to work in the area to the west of the fort that was once the site of the Hudson's Bay Company Village. This area was a densely populated and ethnically diverse neighborhood made up of employees of Fort Vancouver. Excavations will focus on the sites of two Village houses: the house of Little Proulx, a French-Canadian fur trader, and the house of William Kaulehelehe, a Hawaiian educator who served the fort's Hawaiian population. Later, this area was the site of the U.S. Army's Quartermaster's Depot, part of the World War I Spruce Mill, which cut aviation-grade spruce for America's war effort, and a barracks and training compound for the Civilian Conservation Corps (CCC).

Another team of students will be working on the Vancouver Barracks Parade Ground, excavating the site of the historic post's flag staff. A recent study that I put together with Dr. Elizabeth Horton, a National Park Service Archaeologist who recently completed her doctoral dissertation on the historical archaeology of the soldiers and their families at Vancouver Barracks, has identified the location of the 1854-1879 flag staff, which will be the subject of this year's explorations. As Dr. Horton has written, "The colors, or flag, that flew from the post's flag staff was a tangible object that served as a visual reminder of the common group identity of the soldiers on the post. It was a highly significant and symbolic location for the post. All of the early U.S. maps of the post and region measured from the flag staff."

From 9:00 AM to 4:00 PM Tuesday through Saturday, June 24-August 2, the dig sites will be accessible to the public. Members of the public are invited to visit the dig sites and talk with archaeologists and students about this year's finds. Stay tuned for more updates as the excavations unfold for 2014!

Continuing work at the William Kaulehelehe House Site

 The Queen Anne's Lace is still blooming in the area around the William Kaulehelehe House site and we are still finishing up excavations there, although most of the activity has been at the Little Prouxl site.  I spent a bit of time last week doing some finishing up work to close out the small 1 X 5 meter trench that tested the Hawaiian preachers house (Block K).  I had expected to find a few subsurface post and stake holes like we often encounter in the area beneath the dirt floors of the fur trade houses at Fort Vancouver.  After carefully troweling the floor and finding a few minor stains that had little depth and may have been associated with natural processes, I decided that the western-most unit needed at least one more level to make sure that we had not missed anything.  As often happens, this decision led to an increasingly more complex excavation challenge and some very interesting finds.  The eastern margin of the unit contained a nice gray clay, similar to the house floor at the Little Prouxl site, although this was on the outer, western edge of a shallow pit feature that we had excavated earlier in the summer.  Importantly, this clay seemed to dive to the east.  Following this clay proved to be very surprising as what had been thought to be culturally-sterile sediments below the floor turned out to be a fill with a similar color and texture, but that contained a number of artifacts from the house construction including square nails and window glass.

Gilt ring found at the William Kaulehelehe house site.

Interestingly, on the western margins of the clay-lined pit or trench, a man's gilt ring was found. While not of much real value (the gilt is all but gone), this ring is somewhat more fancy than the typical trade rings found at the Fort.  While far from a priceless piece of jewelry, it is intriguing to think that this may have been the personal property of the Hawaiian minister that was lost one day.  One wonders if it had any meaning to him or if he even mourned its loss.

The clay dipped further east into the hole requiring some time to clear.  Surprisingly, a small ceramic sherd was found that has very
rounded edges.  While the transferprint pattern is quite distinctive, the rounding and the small size of the object suggest that it may be an artifact that was subjected to a unique formation process after it was deposited.  Another site associated with the Catholic Mission that we dug on City of Vancouver property about 9 years ago contained similar objects that we interpreted to be gastroliths, or gizzard stones, probably from chickens or some other domesticated fowl.  Birds don't have teeth and to compensate for this, they injest small rocks and other objects (sometimes glass and sometimes ceramics) to help in grinding down their food.  These gizzard stones have been found on archaeological sites before and give a clue, albeit diminutive in size, as to the presence and sometimes the processing of fowl.  

Gastrolith found at the
William Kaulehelehe House Site

On a related note, the clay beneath the ring appears to contain a great deal of bird shot although it is unknown if this represents an area where birds were processed or simply the loss of many very small objects.  In a small test of the clay, I found nearly 50 pieces of shot.

As we had some cloud cover today, I spent a bit of time cleaning up the features of Block K including the newly exposed clay-lined pit/trench and then took photographs to create a 3D model of the test trench.  I made a short YouTube video that you may access at the link below.

YouTube video of 3D Model of Block K

 

Working with the Oregon Archaeological Society

Oregon Archaeological Society Volunteers help out at the Little Proulx site. Staff Elaine
Dorset and Katie Wynia are training the volunteers on the first day.

 Well, the field school is now over and we have begun the next phase of excavations with the Oregon Archaeological Society.  This is a less frenetic pace, as the lecture series is now over, the work at the Spruce Mill is completed and we have volunteers out on Wed, Friday and Saturday. On Tuesdays and Thursdays, we catch up on paperwork and finish work that the volunteers have left us.  We have been working at the Little Proulx site with the volunteers and are completing the removal of the clay-lined house floor.  There is a significant concentration of artifacts in the eastern part of the house and appear to have encountered the western edge of the house floor in units pictured above. Surprisingly we have not yet encountered the hearth.

Key and hardware found at
 the Little Prouxl House Site.

We found a very interesting cupreous fragment that may be part of the lock for a large key found in the adjacent unit.  The size and characteristics of the key appear to match that of a very large door key. This may match the time period when a U.S. Army Surgeon, Levi Holden, occupied the house (early 1850s). The Army rented some of the buildings from the Hudson's Bay Company, including the Little Prouxl house.  Additional information on Holden is listed in an article that was prepared by one of our volunteers last year, Jason Ainsley: http://www.nps.gov/fova/parknews/upload/NCRI-Report_8-2FINALDRAFT.pdf

Royal Coat of Arms of the United Kingdom, found at
the William Kaulehelehe house site.

We are also finishing up work at the William Kaulehelehe house site.  A feature that lines up with the hearth may be a footing feature, which also incidentally lines up nicely with the southern wall of our reconstructed House 1 (the Engage' house).  We appear to be on the north wall of the structure.  On excavation of the area immediately west of this feature, a bit of clay house floor was identified and a curious set of metal fragments.  These appear to be part of a tin (perhaps a tea tin) or the lid to a can or jar.  At first they appeared to have an Irish theme, with a harp and possibly a clover, but on closer examination we have discerned it is the royal coat of arms of the United Kingdom.  As noted by Meagan Huff from the Fort Vancouver Facebook page, "The top fragment is half of a crown, the second from the top contains part of the phrase "Honi soit qui mal y pense," the motto of the Order of the Garter. The fragment third from the top has two barely-visible lions, which represent England. The bottom fragment has a harp, representing Ireland. The banner below it would have contained the words "Dieu et mon droit," the motto of the English monarchs. Research into what this object was for will be ongoing although its presence at a Hawaiian minister's house is quite intriguing with its statement on colonialism and identity with the British empire.

The change in pace has also given me the opportunity to work more closely with the digital forms and iPads to directly explore their use in the field.  A couple of thoughts after a week.  I found the same issues with the glare from the iPads that the students did, particularly when holding them level over the excavation units to attempt to get a plan view of a level or feature.  Even with the brightness increased to maximum, it was difficult at times to get a view of the unit and snap the picture and not lose part of the unit in the image.  This usually required a few shots to get the images I wanted.  Not a huge issue but an aggravation.  The nice thing is that the camera is available at any time for photographing, so I am taking many more images than I would normally.

Another benefit is the ability to use photos to help draw shapes.  Last week I was unhappy with the way in which a mule shoe had been drawn on the house floor by one of the students.  In order to get a better drawing, I took an image of the artifact in-situ, imported it into my level form, then scaled it to the correct size and location, zoomed in and traced the edges of the artifact.  This was done much more accurately and quickly than the hand-drawn method.  I have since tried this method with unit level rocks and the edges of surfaces/floors to improve the quality of the drawings.  I think this has been done to good benefit.  Once the image is traced, the photo is deleted leaving only the line drawing work.

I have been working on some fairly complex levels, with a variety of objects, sampling locations and artifact recording.  The forms seem to take a lot of time, probably longer than a paper form in the field.  The good thing is it is the result is quite legible (a chronic problem for some researchers and students) and the data can be extracted out of the form.  I think I like the annotation  capabilities the best. 

In reviewing the notes from the field school, I have seen that some of the students were quite unhappy with the iDraw program for drawing profiles, and felt they could draw the profiles much faster using paper and pencil (in fact some of them did).  While this may be a factor of unfamiliarity with the program and use of a tablet computer as much as frustration with the speed of entry, there are likely some valid thoughts.  I will explore the use of iDraw to annotate some of these student profiles this week and will report back on its use later.  Regardless, the longest time expended in the field, however, is still the bagging and recording of artifacts, particularly when there are a lot of artifact bags (a typical problem of historical archaeological sites). I will need to think about a means to improve the speed of this process with tablet computers.

Surveying the Spruce Mill Site

Over the past weeks, teams of students have been learning archaeological survey skills at the site of the World War I Spruce Mill, a significant home-front site associated with the processing of old growth Sitka Spruce cut from the forests of the Coast Range of Oregon and Washington and the Olympic Peninsula. 

Besides learning basic pedestrian survey techniques, the crews have also conducted subsurface surveys searching for remnants of the old cut-up mill building, the shops, and tent city for the 3,000 troops that manned the mill. An excellent history of the site by Ward Tonsfeldt helped to guide probing along with remote sensing work by Kendal McDonald reported in an earlier post.

Students excavated probes at locations defined by the magnetometer anomalies recorded earlier in the summer and at locations discovered during monitoring of the removal of some hangars a few years ago. The results confirm that there is abundant evidence of the WWI facility including concrete foundations, concentrations of wire nails and railroad spikes, and even an axe head. Notably, we have been able to see some of the vegetation anomalies associated with the Spruce Mill appearing more distinctive as the ground dries up.

Dry grass in more closely cropped areas suggest where Spruce Mill foundations sit. The ones inside the fort denote where the loading docks to the East and South of the main mill building were located.

The foundations of the sawdust burner are clearly visible as linear dry grass areas adjacent to the reconstructed bake house. 

House Floors, Imaging, and Modelling with Tablet Computers

Over the past two weeks, we have exposed the house floors in both the Little Proulx House and the 1 X 5 m test trench in the WilliamKaulehelehe House.  In both cases, the floors contained evidence of burning consistent with the destruction of both houses by the US Army ca. 1860.  The floors are rich with Hudson’s Bay Company-era artifacts, including beads, buttons, ceramics, vessel glass, window glass, square nails and many other items. There is a very distinctive burnt surface in the eastern half of the Kaulehelehe House site with some evidence of north-south running wooden planks which may indicate a wooden floor that burnt in place or a fallen wall.  In the midst of this rich deposit of artifacts and charred wood and charcoal, a door pintle was found.  This object is of particular importance as it is reported that the U.S. Army removed the windows and door from the Kaulehelehe House prior to torching it on March 20, 1860.  This door pintle and the associated burn layer adjacent to it may be a direct link to the destruction of the house site and the eviction of the Native Hawaiian preacher.

The William Kaulehelehe House site showing the hearth and some preserved planks and charcoal staining.  A door pintle is located in the northern portion of the image.  A water screen sample was previously removed from the southwest corner of the unit and the floor around the hearth has already been excavated.

We had two groups who came to tour the site from the Ke Kukui Foundation.  It was amazing to share these finds with people who have such an interest in Hawaiian heritage and the story of the Hawaiian diaspora.

Dr. Bob Cromwell and I interpret to the Ke Kukui Foundation tour at the Little Prouxl House Site. 

Following the E'se'get Archaeology Project, I decided to capture the hearth using the Autodesk 123D Capture program with my iphone.  As we do not have a 4G connection or wireless access in the field for the iPads, I did not use the tablets for this experiment.  I was quite surprised at the resolution and ease with which 3-D models could be generated in the field.  I took 36 photos of the feature from different angles and submitted them to the Autodesk server that crunched the data in about 15 minutes.  The results were later converted into a video animation on my lap top that I have posted on my University YouTube channel:

YouTube animation of the William Kaulehelehe House Site Hearth (Feature 406)

 As we use the tablet computers, we have begun to discuss improvements to field recording that are facilitated by the concentration of many tools associated with one device.  An obvious improvement would be to take a photograph of the floor of each level as a background for drawing things like rocks, sediment variation, feature boundaries, etc.  Without tablet computers, this is difficult as there are generally only a few cameras on each project.  As each tablet contains a high-resolution camera, it is much easier to collect photographic data on the floor plans (and profiles).  Both the iDraw and pdf Expert apps can import images, although the iDraw app is more sophisticated.  

One issue has been with correcting the distortion caused by cameras that were not placed directly above the floor.  The use of photo-processing apps that remove the distortion (orthorectify the photo) and create a planimetric view may allow a resolution to this problem.  There are a variety of apps available that straighten and flatten images, including programs designed to capture the text and images from whiteboards.  We will be experimenting with some of these apps to improve the capturing of these data.  Simplifying the drawing process may help to streamline the archaeological recovery of data and allow for more sophisticated data to be collected and processed directly in the field. 

Once the distortion is removed, then the picture can be cropped to the size of the unit floor (usually 1 x 1 m) and then dropped into and registered to the image space on the recording form.  Annotations can be placed on top of the image.  For those annotations that were placed prior to the completion of the plan, a translucent image can be generated that will show the earlier details underneath the image.  Theoretically this will free up time drawing things like rocks that are obvious in images, while leaving the ability to annotate those aspects of the floor plan that are not as easy to discriminate with photography.

More on Battery Life

After a week of use, a few statistics can be developed regarding the average use of the iPad and its battery capacity during archaeological excavation.  Table 1 below identifies my tracking of the battery life used each day for the ten iPads. iPads 5, 9 and 10 were only used for the cemetery survey work which only occurred on Thursday and Friday last week.  In addition, Friday afternoon (7/12) was truncated by a lecture and the water screening demonstration so only represent about a 5-hour day.  Due to a glitch, iPads 1 and 2 were not charged the night of 7/9/2013 and the students started 50x50-cm shovel tests (with traditional paper forms) the morning of 7/10/2013 while the units were charging.  iPad 4 was at 8% at 1 pm on 7/10/2013 when it was recharged, therefore only representing about a 4.5 hour work day.

TABLE 1. iPad BATTERY LIFE USED OVER A FIVE-DAY FIELD TEST IN JULY

	7/9/2013			7/10/2013
iPad#	Start	End	Battery Life Used	Start	End	Battery Life Used
1	78	42	36	100	45	55
2	68	3	65	100	84	16
3	100	86	14	86	75	11
4	100	61	39	61	8	53
5	100	100	0	100	100	0
6	81	56	25	100	55	45
7	76	55	21	100	100	0
8	100	59	41	100	67	33
9	100	100	0	100	100	0
10	100	100	0	100	100	0
	7/11/2013			7/12/2013
iPad#	Start	End	Battery Life Used	Start	End	Battery Life Used
1	100	73	27	100	97	3
2	100	50	50	100	79	21
3	100	93	7	100	100	0
4	100	42	58	100	82	18
5	99	24	75	100	37	63
6	100	60	40	100	88	12
7	100	37	63	100	50	50
8	100	68	32	100	48	52
9	100	14	86	100	41	59
10	99	22	77	100	38	62
	7/13/2013
iPad#	Start	End	Battery Life Used
1	100	60	40
2	100	79	21
3	100	99	1
4	100	98	2
5	100	100	0
6	100	40	60
7	100	2	98
8	100	19	81
9	100	100	0
10	100	100	0

As shown in the Table, the cemetery monument recording work, which generates many more forms and digital images, uses up a lot more battery life.  For the two days in which they recorded cemetery headstones, the student's iPads used between 59% and 86% of battery life.  Because Friday was only a five-hour day, and Thursday was a training day when the new crews were getting oriented to the recording strategy, the average battery use might be a bit more for a fully trained crew over an 8 hour workday.  The average for Thursday of 79.3% is probably conservative.  

Ignoring the partial days and charging glitches, the other seven iPads measurements over the five days is 35 observations of battery use.  The average use was 34.0% of the battery with a standard deviation of 24.26.  There was a significant range between no use (the iPad was not used) and 98% of battery use. As iPads are tied to particular excavation units, no use indicates that those units were not excavated that day.  Excavation tasks included filling out the four-page level form, taking images, and some intensive use of iDraw to map the World War I railroad grade. I think a fully trained professional field crew (excavating at a rate of 2 10-cm levels per person per day) will likely generate more forms and perhaps use more battery life depending on the complexity of the site.   Even so, there appears to be plenty of capacity for excavation forms and digital images. This is consistent with the results from other projects, such as the Pyla-Koutsopetria Archaeological Project on Cyprus and the E'se'get Archaeology Project in Nova Scotia.

House Floors, the Spruce Mill, and Other Excavation Notes

Concentration of beads being discovered at the Little Prouxl House Site.

Hearth exposed below house floor
(about 70 cm top to bottom -- west is up)

Over the past two weeks we have been exploring the house floor of the Little Proulx House Site and clearing more units to expand on these excavations.  There have been a number of notable finds, including a cluster of about 70 white beads (what appear to be small, hot-tumbled tube beads) in the southwest corner of one of the excavation units.  The location of this cluster is mapped using the annotation tool on the PDF Expert program. Just to the west of this, a concentration of baked clay (or "bisque" as it is used in the Pacific Northwest, probably from the house fire when it burned), a charred beam, and concentrations of  bisque and charcoal likely associated with the destruction of the house.  In one area nearby, a nicely-defined hearth with a charcoal-black rim and reddish-brown interior was discovered below the clay floor.  This may be a hearth that preceded the construction of the house or an earlier iteration of the structure before the clay floor was
laid down.

We are also shovel probing the Spruce Mill Area, exploring some of the magnetic anomalies identified by Kendal McDonald a few weeks ago.  The probes are about 40 cm in diameter and are dug to at least 50 cm in depth.  The first week of probing we found many interesting strata tied to fill associated with the World War I mill site and later uses of the property for aviation and other U.S. Army and City of Vancouver uses. We found surprisingly few metal objects or other sources that could be tied to the anomalies.  This past week we used a metal detector to really home in on the magnetic sources and were rewarded with many metal objects, including cast spikes, a likely aviation fuel line, and other objects.

Excavation of a shovel probe at the Spruce Mill cut-up mill site.
Pearson Air Museum, including the repurposed World War I hanger  in the background.

Back at the dig site, we used iDraw to map the top of one of the World War I Spruce Mill spur lines that rest above the Little Prouxl House Site.  Besides being an excellent training excercise, we are troubleshooting the use of iDraw for illustration of plan and profile maps.

Battery Life in the Field

One of the concerns raised by some with the use of tablets in the field was battery life and if the tablets would last through an entire day of field recording. I am happy to report that battery usage during excavation is about 20-40% during the day depending on the number of forms worked on. While the school is digging more slowly than a professional crew in the field, it appears that there is plenty of juice to record excavation data without having a supplemental source or having to swap out units.

In contrast, the cemetery recording project uses up an entire battery each day. One tablet ran out of juice before the final photos of monuments were recorded. This is undoubtedly due to the much larger number of forms created each day during cemetery recording.

By recording battery life each day, we should be able to get some metrics on the number of forms generated contrasted with battery expenditure. This week I will collect some data.

Survey Crew Starts Work at Spruce Mill

As part of the Field school, the students learn skills in field surveying to discover and record archaeological sites, including basic orienteering and gps, pedestrian and subsurface shovel probing, and mapping and site recording.  This week, a quarter of the field school started this portion of the course under the direction of Tony Hofkamp.  The site of this course is the field east of the reconstructed fur-trade fort and west of Pearson Air Museum.  This was the location of the World War I Spruce cut-up mill.

Last week Kendal McDonald (Z-Too Archaeogeophysical Prospection and Applied Archaeological Research) collected remote sensing data from the Spruce Mill area using her gradiometer (see Remote Sensing post from last week).  She was able to get us some preliminary results from the 160 m long north-south by 20 m wide transect we set up across the Cut-up mill. There are some dramatic patterns in magnetic anomalies that the survey crew will explore over the next four weeks.

While we excavated over a dozen probes this week, we have not had good fortune hitting the source of some of the anomalies. Next week I plan to use a metal detector to refine the locations for probes

Kendal McDonald shows Field School the results of the
Gradiometer Survey in the Field Laboratory

Magnetometer Results laid out on the Laboratory Floor.  Some of the strong positive-negative
linear anomalies may be buried cables for aircraft ties from the later airport.

Bag Catalogs and the Field Laboratory

Yesterday we started our field laboratory portion of the course.  Students will cycle through the field lab to gain basic skills in organizing, cleaning, and error-checking the collections and archival materials. When we were designing the digital forms we made the conscious decision to only maintain a bag catalog tied to the level and feature forms and to not have a separate bag catalog for artifact bags collected from each unit.  While this removes an aspect of redundancy which is designed to avoid errors, it was thought that the digital forms would facilitate the creation of a bag catalog in the field laboratory to assist in error checking, and building a site-wide artifact catalog.  On Monday, while the Field School rested, I explored how to go from the adobe forms to excel to create a usable bag catalog. The pdf forms can be extracted to an excel spreadsheet with ease and it is simple to extract the data from each level form as a row (single line on a relational database) tied to individual units.  To then use these data to create an inventory of bags collected, I wrote a short macro using Visual Basic which primarily uses a For Next routine to collect the six variables collected for each bag, including its bag number, type of artifact (e.g., beads, transferprint ceramic, etc.), the field count of artifacts in the bag, and if it was point-provenienced, the northing, easting, and elevation of that object.  The routine simply copies these data for each level form listed on the excel worksheet as a line to a new bag catalog worksheet.  At this point there is still a bit of cleanup necessary to sort the bags to remove blank spaces between levels and I had to add a "level" field that we are adding by hand in the lab during error checking.  When I get a free moment I will work on the macro to attempt to further streamline these processes.  We are starting to use these "bag catalogs" in the field lab to create lot and specimen numbers to track the collections through the cleaning, analysis, and cataloging process.  Stay tuned for how it will work out!

Remote Sensing

Today Kendal McDonald will finish a magnetometer survey of the World War I Spruce Mill site east of the reconstructed fort. On Wednesday, Kendal conducted a workshop with the students on the main parade ground and then collected data from a 20 X 20 m square on the suspected site of the original US Army flag pole. Kendal's magnetometer is a Geometrics G-858 dual sensor cesium magnetometer configured as a gradiometer. She records the magnetic signature of the sediments she walks over and contrasts it with the magnetic "noise" of overhead power lines, solar radiation, and other intrusive magnetic disturbance. The resulting magnetic gradient between the two is used to look for changes in the sediment magnetic signature tied to metal objects, old pits, hearths, and foundations. 

Besides the flag pole location, we hope to find foundations, rail lines and other remains of the spruce mill. The mill cut spruce logged from the coast range into pieces suitable for making aircraft during the Great War.

Upon us all a little rain must fall

Today we started our second week in the field at the Fort Vancouver Village. It rained quite a bit over our Sunday-Monday "weekend" and continued off and on with showers today. While there was never a steady rain, there were lots of drips off the shelters and students got to try out their rain gear.

The iPads held up nicely in moist conditions and we verified that it is possible to use them inside a clear sealable plastic bag. On Monday I updated the form templates to correct a glitch in the other materials observed but not collected category. I also developed a simple photo log form to collect the information we need for each iPads photo images.

The crew on Block L (Little Prouxl's House) started removing 5 cm of the house floor. They are finding some Hudson's Bay Company artifacts and some larger animal bones tied to the house. Some remnants of the gray clay floor remain from last year and the students are removing these patches. 

In the morning we had a visit from some Oregon Museum of Science and Industry (OMSI) campers who are learning about the science of archaeology for 1/2 a week and then heading out to John Day fossil beds for 1/2 a week.

The campers helped screen and the students helped to explain some of the common field tasks like excavation and plan mapping. The students also showed the use of the iPads in field recording.