A treasure trove of archives missing for 40 years has begun arriving in New York, and historians say it is a window on the vanished world of Eastern European Jews.

It includes eyewitness accounts of brutal Ukrainian pogroms, a schedule of lectures at a rabbinical school in Lithuania, and a collection of such village superstitions as: "If a pig carries straw in her mouth, there will be rain."The 200 boxes of records, collected before World War II and presumed lost during the Nazi era and the Cold War, turned up in Lithuania's National Library two years ago.

About a third of the collection arrived in New York on Wednesday, and historians from YIVO, the Institute for Jewish Research, began combing through the material Thursday at their Manhattan offices.

It will take months to organize. The disorderly state of the archives, says YIVO Research Director Allan Nadler, is "almost symbolic of what happened to the Jews of Eastern Europe. Chaos. Torn pieces of paper. Fragments. Confusion."

A cursory look already has turned up many gems, including a portrait sketched and signed by Pablo Picasso of a popular Yiddish artist, Mane-Katz.

There's also a copy of a 1929 letter from Albert Einstein, who was a member of YIVO's board of directors, expounding on the importance of preserving "the spiritual and moral traditions of the Jewish people."

A collection of tattered Yiddish documents, some in neat handwritten script and others typed, include eyewitness accounts of pogroms waged against Ukrainian Jews between 1918 and 1920.

One paper painstakingly lists all 187 victims of a pogrom in the town of Dubova in 1919, from the 82-year-old rabbi, Moshe Aaron Bertochefsky, to 4-year-old Liba Liepas, the miller's granddaughter.

YIVO was formed in 1925 in Vilna, in what was then Poland; today it is called Vilnius and is the capital of Lithuania.

With the outbreak of World War II, the organization relocated to Manhattan; some of its archives were taken to Paris and then New York, and some were found in Germany after the war.

Historians assumed that the rest of the documents had been destroyed or lost. When they were found in the National Library in Vilnius in 1993, "no one there knew what the stuff was because the vast majority is in Hebrew script, and they couldn't read it," Nadler said.