November 24, 2017

North of the 19th Street BART station, the tracks curve left and emerge on the north side of 23rd Street. This is one of two access covers on 22nd Street, right next to the parking structure, that lead into the underground. I never really noticed them until one day I heard a train go by down below. Haven’t heard one since.

Perhaps there are other examples elsewhere in the system. Let’s keep track here in the comments.


Some stamps from Berkeley 2

November 17, 2017

Having spent a lot of time walking in Berkeley lately, I’ve collected a few more stamps bearing dates unrepresented in Oakland.

1906 – Esterly Con. Co.

1529 Le Roy Avenue

A fine double mark, though the date is dim. Oakland has a double mark from 1907.

1908 – Esterly Con. Co.

1529 Le Roy Avenue

Both of these Esterly marks are on the Hayward Fault, so it’s not clear how much longer they’ll last.

1921 – J. E. Reed

1631 Spruce Street

Oakland has a single example of Reed’s mark, barely over the Berkeley line.

1958 – G. W. Griset

2285 Virginia Street

Griset’s marks are fairly common in Oakland, but they span only a few years from 1950 to 1957.

Tessellations in concrete

November 10, 2017

A tessellation is a set of polygons that fills a plane without gaps or overlaps. Pavement makers often draw grooves in patterns like this example from Piedmont; I think one reason is to help the concrete break unobtrusively, along the grooves, rather than spiderwebbing all over a nice clean driveway. Another reason would be to help out the next worker who has to patch or repair the job by enabling them to cut the old concrete neatly. But mainly I think it’s just to show artisanship and decorate something utilitarian.

As a geologist, I look at this and infer a sequence of events. First came the sidewalk, installed by the developer. Then came the main part of the driveway, where the concrete worker tried to tie the tessellation to the divisions in the sidewalk and also tried to match the sidewalk’s color. Then came the worker who widened the driveway. He exercised less care in matching the colors, and less creativity in drawing grooves.

I also like the pattern of stones in the wall behind the driveway. Wallmaking is a whole nother expert art.

Mathematicians don’t care about haphazard tessellations like these. They’re fascinated by more challenging tessellations with some degree of order, or tessellations that can extend to infinity or wrap around curved surfaces and so on. You can get a dizzying taste of the subject at Wikipedia.

Polygons, by definition, have straight sides. Many sidewalk makers cover their work with curved grooves, and some time I’ll post a few examples. Those might conceivably be called tessellations, but I think I’ll just call them space-filling exercises.

American Brotherhood of Cement Workers

November 3, 2017

I know I’ve talked about the A.B.C.W. before — read that post for the living connection to today — but this week’s post is just to record a splendid example of the sidewalk stamp, in Berkeley at the corner of Shasta and Tamalpais Roads.

The sidewalks paved by the Oakland Paving Company’s union workers, everywhere I’ve seen them, are second to none. A hundred years old and they’re strong as ever. And the design shows such pride. A hundred years from now the concrete being poured today might match this old stuff in strength, but the new sidewalks will never match the old ones in character.

Sidewalk maker: J. O. Adler

October 27, 2017

John Olaf Adler was born in Sweden in 1857 and emigrated to the United States around 1880. He soon made his way to the thriving port city of San Francisco, where he became a citizen in 1886 and married Helena (Lena) Nilson in 1887. They were to have two daughters, Hulda and Mamie.

He was a career seaman, mentioned in the Call or listed in the San Francisco directories for 20 years as a ship’s officer on many different steamers serving the west coast ports: the San Vicente in 1887, the Point Arena in 1891, the Eureka in 1896, the Del Norte in 1899, the Celia in 1901, the Coquille River in 1905 and the Greenwood as of March 1906. He kept up his master’s license as late as 1919, when this photo was taken (thanks, He had blue eyes and tattoos on both forearms.

By 1896 he had moved his family across the bay to the town of Lorin, which became part of Berkeley soon after. The Adlers lived at 3040 Adeline, where the Ashby BART station sits, from 1900 until his death in 1926.

Around this time he got into the concrete business, according to the city directories. I’ve recorded his stamp in Oakland with dates from 1910 to 1916. Presumably other years are preserved in Berkeley. All of them look like the example above, except for this outlier from 1915.

I suspect, but cannot yet confirm, that he was the Adler of Adler and Peterson, the firm that left Oakland’s oldest surviving sidewalk stamps (from 1901 and 1907).

John and Lena Adler are buried at Mountain View Cemetery. She died in 1924, and it appears that her gravestone was moved on top of his when he died. He had remarried by the time of his death, and Anna survived him.

Baypoint Iron Works access cover

October 20, 2017

This rarity sits in the street where Highland and Wildwood Avenues meet, in Piedmont. Port Chicago was the former town just west of Bay Point where the terrible explosion of 17 July 1944 occurred. The Baypoint Iron Works existed at that time, but I have found no information about it beyond that fact. The town was taken over by the government and demolished in 1968.

Sidewalk maker: A. Soda

October 13, 2017

Andrea Soda was born in southern Italy, near Provenza, in 1877, and came to America in 1907 with his wife Margherita (nee Argenta). He was listed in the 1908 directory as a cement worker. By 1912 he was living at 1137 65th Street, the address shown in his sidewalk stamps, and was the father of three children. He went by the name Andre or Andrew, and his wife likewise was called Marguerite or Margarita.

His draft form from 1917 described him as a man of medium height and build, with blue eyes and dark hair and not yet a naturalized citizen.

I have documented his marks from 1913 to 1937, all using the stamp shown above. The Tribune records him bidding on various jobs under the name A. Soda Company from 1928 to 1931 and A. Soda & Son (or Sons) from 1932 to the 1950s. (His sons were Yster Charles (“Y. C.” or Chester), born in 1908, and Stephen, born in 1912.) The company’s contracts grew in size over the years and came to focus on small bridges around Northern California.

On 5 November 1936, the firm was retimbering the old high-level tunnel above today’s Caldecott Tunnel when a collapse killed one of his workers. The paper quoted Y.C. as saying the firm had never, not once had such an accident before, and also noted that his workers kept photographers away from the scene. By this time Andrea had moved to Sacramento Street in Berkeley, with Chester still living at the old homestead.

By the 1940s Andrea had retired from the Soda firm and was running a liquor store at 6324 San Pablo Avenue. He died in 1948. Several family members, including Margherita, are entombed in a family crypt at Holy Sepulchre Cemetery in Hayward, but I can’t tell if he’s there too.

I was prompted to compose this post by spotting an A. Soda mark in Berkeley from 1916, a year not found in Oakland.

2099 Martin Luther King Jr. Way