Speakers List
Are you looking for a guest speaker for your conference, event, or webinar? Below is a list of available presentations by Clinton County Historical Association volunteers.
To book a speaker, please contact:
Helen Nerska, Director,
Clinton County Historical Association
Call or text: 513-582-7246
Email: [email protected]
To book a speaker, please contact:
Helen Nerska, Director,
Clinton County Historical Association
Call or text: 513-582-7246
Email: [email protected]
Struggle in the Snow: The Storming of Quebec with Military Historian Thaddeus Booth-Trudo. New Year’s Eve 2025 was the 250th Anniversary of the attempted storming of Quebec City by American forces under the command of Generals Richard Montgomery and Benedict Arnold. Learn more about this event and the brave patriots who participate in this early revolutionary war battle.
From Quebec to Valcour with Military Historian Thaddeus Booth-Trudo. Learn about the intervening events and connections between the 1775-1776 invasion of Canada and the Valcour Campaign of 1776.
The Battle of Valcour Island – before, during and after. With Reenactor and Historian Craig Russell. Hear the story of the most important naval battle of the Revolutionary War – fought on our lake on October 11, 1776.
Churubusco and the 1837 Rebellion with Town of Clinton Historian Rebecca LeClair discusses the unique demographics of the Town of Clinton (Churubusco). This presentation will reveal why the Churubusco populus is primarily French Canadian and Irish by delving into the history of settlement in Churubusco and how it ties into the Canadian rebellion of 1837!
Town of Peru Settlers before the Revolution – Not Just William Hay in 1772. People and Stories never before revealed with Historian David Glenn.
The Grange Movement in Clinton County and its Legacy. Beginning in Mooers in 1897, the Grange Movement quickly spread throughout Clinton County providing access to what was declared in the Plattsburgh Sentinel in 1904 to be one of the "grandest educational organizations in the world." Welcoming both men and women into their organizational hierarchy, granges and their leaders built halls, published histories, held educational forums and hosted community events throughout Clinton County. Helen Nerska, the daughter of a 'granger' shares her research on the impact of this county-wide movement.
The Extraordinary Life of Champlain’s Jehudi Ashmun (1794 – 1828). Born and raised in Champlain, New York, Jehudi Ashmun went on to help the American Colonization Society successfully establish Liberia. The story of his journey from Champlain to Liberia is the story of the life of an extraordinary man from the North Country.
Redford Glass Uncovered. The presentation will take participants back to a period more than 200 years ago to learn about the short-lived history of the Redford Glass Company. Although the company was in business for only 20 years they produced products that demonstrated unique skilled craftsmanship that survive to this day. By the end of the presentation participants will see how the Company, that was once famous and esteemed for its crown glass windowpanes, has become synonymous with unique and priceless glassware.
History of Clinton County in Pictures. Where did the County start and how did it develop. See photos of the towns and villages which formed to become part of the Clinton County story. With Helen Nerska.
Slavery & the Underground Railroad in New York and the North Country - provides information on the role of slaves in New York and the North Country and how they arrived in the area. Attendees learn the stories of abolitionists and freedom seekers, as well as how this route is used by immigrants today. With North Country Underground Railroad Historical Association President Jacqueline Madison.
Underground Railroad in the Lake Champlain Region - tells how the start of the freedom seekers using this area to make their way to Canada opened up those routes for future generations. The North Star Underground Railroad Museum is known for formerly enslaved individuals going into Canada but this area had tales of others who used this route to go into Canada or to get into America that started after the Civil War. With North Country Underground Railroad Historical Association President Jacqueline Madison.
People of Color in the Lake Champlain Region - tells the stories of African Americans, Asians and Indigenous People who lived, worked and thrived in the community. While some individuals were slaves, others came to make a better life for themselves and their families. With North Country Underground Railroad Historical Association President Jacqueline Madison.
Two Battles, One Ballot: African American Women and the Struggle for Equal Voting Rights - America at 250: The Promise of Equality - showcases the struggle African American women went through to get the right to vote. They fought two battles, sex and race, while trying to make the statement, "All men are created equal,” really stands for all people. With North Country Underground Railroad Historical Association President Jacqueline Madison.
Building Plattsburgh City Hall and the Macdonough Monument: their design and construction as told in photos from the Clinton County Historical Association's Collection with Helen Nerska.
Portraits and Painters of the Early Champlain Valley (1800-1865) with Helen Nerska. Slides from a 1975 SUNY Plattsburgh exhibit with reflections on the history of the painters and the lives of the sitters. Attendees are encouraged to bring photos of old paintings they might have and share the history of their paintings.
Maple Sugaring: More Than Just a Sweet Tradition. Explore the history of maple sugaring. We will look beyond the Native Peoples and modern methods to the political and social impacts of maple production with Kristina Parker, Altona Town Historian.
Profiles from Portraits. From the Clinton County Historical Association’s collection, see portraits of men once posted at the Plattsburgh Barracks whose uniforms hint at their military history uncovering special stories yet to be told with Military Historian Thaddeus Booth-Trudo.
The Davidson Sisters: Darkness and Light. Local teenaged poets and sisters, Lucretia and Margaret Davidson, were once known nationwide as tragic and romantic figures in the literary world. Through anecdotal stories, journal entries, letters, and their own works, Author and teacher Lisabeth Guay shares insights into who these two extraordinary young ladies of Plattsburgh once were.
Stories of Amazing Women – with Helen Nerska. The stories of Suffragist and community Leader Marie Parkhurst Booth and the first female State Judge Luella Robinson North.
Catholic Summer School of America with Robin LaBarge. Hear the story and see photos of the school which dominated the landscape of Cliff Haven from 1893 to 1950 and attracted thousands of summer visitors to the Plattsburgh area.
Stories of Amazing Women with Pat Loughan, President of the Kent-Delord House Museum. Highlighting the extraordinary lives of Historian Jeannette Tuttle and teacher Helene Augustin using collection photos and local histories to tell the stories.
The Legacy of the location with the most beautiful view - photos and stories of the history of Bluff Point and the Hotel Champlain. Built by the D&H Railroad and frequented by Presidents, the hotel was one of the most prestigious vacation sites in America. See its history and beauty in photos from the Clinton County Historical Association's own collection. With Helen Nerska.
A virtual tour and history of the Plattsburgh Memorial Chapel with Kate Chilton and Helen Nerska. See photos and hear the stories of the creation of this memorial to veterans who trained in Plattsburgh and who died in the Great War.
Portraits from the turn of the 19th century and the stories they might tell. CCHA has 17,000 portraits in their collection taken between 1890 and 1920, and some of the most unusual and interesting will be shared along with the known or occasionally speculated background behind the photo. With Helen Nerska.
Remembering the Ladies. Abigail Adams famously charged her husband to “remember the ladies” as he worked to reform colonial government in early 1776. Though rarely on the battlefield, many American women were as invested in the success of the Revolution as the men who led and died in the war. Their contributions from the homefront to the front lines established their place as partners in the new nation. Presented by Dr. Wendy Gordon, History Professor, SUNY Plattsburgh
A Photo Peek at Old Plattsburgh. Using photos from the CCHA collection, see ‘then and now’ photo comparisons of landmarks in downtown Plattsburgh. Come and see what you might recognize and share stories of these special spots. With Helen Nerska.
The Golden Age of the Cigar Trade in Downtown Plattsburgh. For over 75 years thousands of cigars were produced in downtown Plattsburgh. Hear the story of our own flourishing cigar industry and the families that managed it using photos and artifacts from the CCHA Collection. With Helen Nerska.
William Henry Miner and His Lasting Legacy in the North Country with Amy Bedard. William Henry Miner’s life is a true Horatio Alger story. Orphaned as a pre-teen, Miner was sent from the Midwest to live with his aunt and uncle in Chazy, New York. Miner returned to the Midwest as a young man and eventually became a successful inventor of railroad equipment by the late 19th century. After achieving his wealth, Miner returned to Chazy with his wife Alice to establish Heart’s Delight Farm. The farm was a model of agricultural innovation and self-sufficiency. The Miners also believed in using their fortune to help others and their remarkable generosity continues to impact the North Country.
"Exploring Plattsburgh's Point: The Buildings of the Macomb St. Historic District." With Dr. James Lindgren, Professor Emeritus, SUNY Plattsburgh. Examining the city's East End, this presentation traces the development of the area's historic architecture: the various styles of buildings, their contributions to the extended historic district, and the status of their preservation.
"Revisiting the Brinkerhoff & Court Street Historic Districts: Gains, Omissions, and Losses over 50 Years." With Dr. James Lindgren, Professor Emeritus, SUNY Plattsburgh. With the passage of the National Historic Preservation Act of 1966 and the many threats to Plattsburgh's rich cultural heritage in those years, Dr. Allan Everest and the Clinton County Historical Association jump-started a drive in the 1970s to protect endangered architecture in the city center. Their work led to the creation of four National Register Historic Districts, which included two very different districts on Brinkerhoff and Court Streets in 1982. This illustrated presentation assesses what was included, how it changed over the years, and the many issues still facing both districts.
Walk Around the Block – a photographic view of the Plattsburgh City Center in the late 19th and early 20th Centuries with Pat Loughan, President, Kent-Delord House Museum.
"Lost Plattsburgh: Our Missing Architectural Roots" Focusing on the architecture and importance of Plattsburgh buildings destroyed by fire or willful act, and picking up where Allan Everest left off in Our North Country Heritage (1972), the presentation discusses how their loss has left a lamentable gap in our nineteenth- and twentieth-century history. With Dr. James M. Lindgren, Professor Emeritus, SUNY, Dept. of History
Riddle me this!! – Test yourself and learn something new with questions and answers about the County’s rich history with a prize for the winner. With Helen Nerska.
Discovering the Town of Peru. First settled by Europeans in 1772 and established as a town in 1792, Peru’s history timeline reflects how small north country towns were created and developed into thriving villages. With Peru Town Historian, Helen Nerska.
The Clinton County Suffrage Story with Helen Nerska. After nearly 70 years of persuasion, New York State allowed women to vote in all elections. Hear the stories of the many Clinton County women and men who dedicated themselves to achieving this right for women.
A Virtual Tour of the Old Base Oval with Helen Nerska showing photos of the original buildings and the histories associated with each.
The Life and Times of Fannie Delord Hall with Pat Loughan, President, Kent-Delord House Museum.
Remembering Clinton County’s World War I Veterans and the Hometown celebrations which welcomed them back. Introducing the Clinton County WWI Record 1917-1919 and the story of the impact of World War I on the Clinton County Community. With Helen Nerska based on research by CCHA Past President Noel Stewart.
A Jury of Your Peers. Women received the right to vote across the nation in 1920 but not the right to be on a jury until years later. Learn the struggle for and gradual acceptance of women on juries. With Helen Nerska.
History of Standish, New York. With author and historian Marissa Dandrow. Explore the history of Standish through its industries, businesses, residents, population changes and immigration, major events, and the everyday stories that made it one of the Adirondacks' most fascinating iron villages. Includes some of the history of Standish's Black and multiracial residents.
The Booming Blueberry Business on the Altona Flat Rock (1850-1957)
Did you know that for more than a century, local families traveled to the Altona Flat Rock each summer to harvest wild blueberries and earn extra income? These prized berries were shipped to markets in Boston, New York City, and beyond, helping to create a thriving seasonal industry in the North Country. What made the Altona blueberries so special, and why did this once-booming business disappear in 1957? Join local history enthusiast Steven Frederick as he shares the fascinating story of the mighty blueberry and its important role in our region's past.
Manufacturing in Clinton County Since 1831
Long before Clinton County became a modern manufacturing center for aerospace and transportation industries, local factories and workshops were producing goods that helped build America. This engaging presentation explores nearly two centuries of manufacturing history, featuring products such as typewriters, sewing machines, automobiles, horse nails, apple barrels, fine furniture, and more. Through rare historic photographs, including black-and-white glass plate negatives from the Clinton County Historical Association, attendees will discover what life was like for early factory workers, how industries evolved over time, and the often challenging and hazardous conditions they faced. Join local history enthusiast Steven Frederick for a fascinating pictorial journey through Clinton County's industrial past.
History of The Chateaugay Railroad. With author and historian Marissa Dandrow. The Chateaugay Railroad was the first railroad to reach the heart of the Adirondacks, and it played a major role in boosting Adirondack tourism. It began as an industrial narrow-gauge railroad that was well suited to the area's mountainous terrain. The ride itself was a thrill, winding around mountains and lakes, traveling in every direction on the compass to maintain a feasible grade. The railroad connected the Chateaugay ore bed to Plattsburgh, where ore barges and D&H trains could transport the products throughout the United States. It also brought workers, supplies, and goods to the remote villages of the ore bed and Chateaugay Woods. Starting in 1880, the railroad capitalized on Adirondack tourism, becoming a powerhouse for both pleasure and health tourism. It reached Loon Lake in 1886, Saranac Lake in 1887, and Lake Placid in 1893. Come learn more about this history-making railroad.
From Quebec to Valcour with Military Historian Thaddeus Booth-Trudo. Learn about the intervening events and connections between the 1775-1776 invasion of Canada and the Valcour Campaign of 1776.
The Battle of Valcour Island – before, during and after. With Reenactor and Historian Craig Russell. Hear the story of the most important naval battle of the Revolutionary War – fought on our lake on October 11, 1776.
Churubusco and the 1837 Rebellion with Town of Clinton Historian Rebecca LeClair discusses the unique demographics of the Town of Clinton (Churubusco). This presentation will reveal why the Churubusco populus is primarily French Canadian and Irish by delving into the history of settlement in Churubusco and how it ties into the Canadian rebellion of 1837!
Town of Peru Settlers before the Revolution – Not Just William Hay in 1772. People and Stories never before revealed with Historian David Glenn.
The Grange Movement in Clinton County and its Legacy. Beginning in Mooers in 1897, the Grange Movement quickly spread throughout Clinton County providing access to what was declared in the Plattsburgh Sentinel in 1904 to be one of the "grandest educational organizations in the world." Welcoming both men and women into their organizational hierarchy, granges and their leaders built halls, published histories, held educational forums and hosted community events throughout Clinton County. Helen Nerska, the daughter of a 'granger' shares her research on the impact of this county-wide movement.
The Extraordinary Life of Champlain’s Jehudi Ashmun (1794 – 1828). Born and raised in Champlain, New York, Jehudi Ashmun went on to help the American Colonization Society successfully establish Liberia. The story of his journey from Champlain to Liberia is the story of the life of an extraordinary man from the North Country.
Redford Glass Uncovered. The presentation will take participants back to a period more than 200 years ago to learn about the short-lived history of the Redford Glass Company. Although the company was in business for only 20 years they produced products that demonstrated unique skilled craftsmanship that survive to this day. By the end of the presentation participants will see how the Company, that was once famous and esteemed for its crown glass windowpanes, has become synonymous with unique and priceless glassware.
History of Clinton County in Pictures. Where did the County start and how did it develop. See photos of the towns and villages which formed to become part of the Clinton County story. With Helen Nerska.
Slavery & the Underground Railroad in New York and the North Country - provides information on the role of slaves in New York and the North Country and how they arrived in the area. Attendees learn the stories of abolitionists and freedom seekers, as well as how this route is used by immigrants today. With North Country Underground Railroad Historical Association President Jacqueline Madison.
Underground Railroad in the Lake Champlain Region - tells how the start of the freedom seekers using this area to make their way to Canada opened up those routes for future generations. The North Star Underground Railroad Museum is known for formerly enslaved individuals going into Canada but this area had tales of others who used this route to go into Canada or to get into America that started after the Civil War. With North Country Underground Railroad Historical Association President Jacqueline Madison.
People of Color in the Lake Champlain Region - tells the stories of African Americans, Asians and Indigenous People who lived, worked and thrived in the community. While some individuals were slaves, others came to make a better life for themselves and their families. With North Country Underground Railroad Historical Association President Jacqueline Madison.
Two Battles, One Ballot: African American Women and the Struggle for Equal Voting Rights - America at 250: The Promise of Equality - showcases the struggle African American women went through to get the right to vote. They fought two battles, sex and race, while trying to make the statement, "All men are created equal,” really stands for all people. With North Country Underground Railroad Historical Association President Jacqueline Madison.
Building Plattsburgh City Hall and the Macdonough Monument: their design and construction as told in photos from the Clinton County Historical Association's Collection with Helen Nerska.
Portraits and Painters of the Early Champlain Valley (1800-1865) with Helen Nerska. Slides from a 1975 SUNY Plattsburgh exhibit with reflections on the history of the painters and the lives of the sitters. Attendees are encouraged to bring photos of old paintings they might have and share the history of their paintings.
Maple Sugaring: More Than Just a Sweet Tradition. Explore the history of maple sugaring. We will look beyond the Native Peoples and modern methods to the political and social impacts of maple production with Kristina Parker, Altona Town Historian.
Profiles from Portraits. From the Clinton County Historical Association’s collection, see portraits of men once posted at the Plattsburgh Barracks whose uniforms hint at their military history uncovering special stories yet to be told with Military Historian Thaddeus Booth-Trudo.
The Davidson Sisters: Darkness and Light. Local teenaged poets and sisters, Lucretia and Margaret Davidson, were once known nationwide as tragic and romantic figures in the literary world. Through anecdotal stories, journal entries, letters, and their own works, Author and teacher Lisabeth Guay shares insights into who these two extraordinary young ladies of Plattsburgh once were.
Stories of Amazing Women – with Helen Nerska. The stories of Suffragist and community Leader Marie Parkhurst Booth and the first female State Judge Luella Robinson North.
Catholic Summer School of America with Robin LaBarge. Hear the story and see photos of the school which dominated the landscape of Cliff Haven from 1893 to 1950 and attracted thousands of summer visitors to the Plattsburgh area.
Stories of Amazing Women with Pat Loughan, President of the Kent-Delord House Museum. Highlighting the extraordinary lives of Historian Jeannette Tuttle and teacher Helene Augustin using collection photos and local histories to tell the stories.
The Legacy of the location with the most beautiful view - photos and stories of the history of Bluff Point and the Hotel Champlain. Built by the D&H Railroad and frequented by Presidents, the hotel was one of the most prestigious vacation sites in America. See its history and beauty in photos from the Clinton County Historical Association's own collection. With Helen Nerska.
A virtual tour and history of the Plattsburgh Memorial Chapel with Kate Chilton and Helen Nerska. See photos and hear the stories of the creation of this memorial to veterans who trained in Plattsburgh and who died in the Great War.
Portraits from the turn of the 19th century and the stories they might tell. CCHA has 17,000 portraits in their collection taken between 1890 and 1920, and some of the most unusual and interesting will be shared along with the known or occasionally speculated background behind the photo. With Helen Nerska.
Remembering the Ladies. Abigail Adams famously charged her husband to “remember the ladies” as he worked to reform colonial government in early 1776. Though rarely on the battlefield, many American women were as invested in the success of the Revolution as the men who led and died in the war. Their contributions from the homefront to the front lines established their place as partners in the new nation. Presented by Dr. Wendy Gordon, History Professor, SUNY Plattsburgh
A Photo Peek at Old Plattsburgh. Using photos from the CCHA collection, see ‘then and now’ photo comparisons of landmarks in downtown Plattsburgh. Come and see what you might recognize and share stories of these special spots. With Helen Nerska.
The Golden Age of the Cigar Trade in Downtown Plattsburgh. For over 75 years thousands of cigars were produced in downtown Plattsburgh. Hear the story of our own flourishing cigar industry and the families that managed it using photos and artifacts from the CCHA Collection. With Helen Nerska.
William Henry Miner and His Lasting Legacy in the North Country with Amy Bedard. William Henry Miner’s life is a true Horatio Alger story. Orphaned as a pre-teen, Miner was sent from the Midwest to live with his aunt and uncle in Chazy, New York. Miner returned to the Midwest as a young man and eventually became a successful inventor of railroad equipment by the late 19th century. After achieving his wealth, Miner returned to Chazy with his wife Alice to establish Heart’s Delight Farm. The farm was a model of agricultural innovation and self-sufficiency. The Miners also believed in using their fortune to help others and their remarkable generosity continues to impact the North Country.
"Exploring Plattsburgh's Point: The Buildings of the Macomb St. Historic District." With Dr. James Lindgren, Professor Emeritus, SUNY Plattsburgh. Examining the city's East End, this presentation traces the development of the area's historic architecture: the various styles of buildings, their contributions to the extended historic district, and the status of their preservation.
"Revisiting the Brinkerhoff & Court Street Historic Districts: Gains, Omissions, and Losses over 50 Years." With Dr. James Lindgren, Professor Emeritus, SUNY Plattsburgh. With the passage of the National Historic Preservation Act of 1966 and the many threats to Plattsburgh's rich cultural heritage in those years, Dr. Allan Everest and the Clinton County Historical Association jump-started a drive in the 1970s to protect endangered architecture in the city center. Their work led to the creation of four National Register Historic Districts, which included two very different districts on Brinkerhoff and Court Streets in 1982. This illustrated presentation assesses what was included, how it changed over the years, and the many issues still facing both districts.
Walk Around the Block – a photographic view of the Plattsburgh City Center in the late 19th and early 20th Centuries with Pat Loughan, President, Kent-Delord House Museum.
"Lost Plattsburgh: Our Missing Architectural Roots" Focusing on the architecture and importance of Plattsburgh buildings destroyed by fire or willful act, and picking up where Allan Everest left off in Our North Country Heritage (1972), the presentation discusses how their loss has left a lamentable gap in our nineteenth- and twentieth-century history. With Dr. James M. Lindgren, Professor Emeritus, SUNY, Dept. of History
Riddle me this!! – Test yourself and learn something new with questions and answers about the County’s rich history with a prize for the winner. With Helen Nerska.
Discovering the Town of Peru. First settled by Europeans in 1772 and established as a town in 1792, Peru’s history timeline reflects how small north country towns were created and developed into thriving villages. With Peru Town Historian, Helen Nerska.
The Clinton County Suffrage Story with Helen Nerska. After nearly 70 years of persuasion, New York State allowed women to vote in all elections. Hear the stories of the many Clinton County women and men who dedicated themselves to achieving this right for women.
A Virtual Tour of the Old Base Oval with Helen Nerska showing photos of the original buildings and the histories associated with each.
The Life and Times of Fannie Delord Hall with Pat Loughan, President, Kent-Delord House Museum.
Remembering Clinton County’s World War I Veterans and the Hometown celebrations which welcomed them back. Introducing the Clinton County WWI Record 1917-1919 and the story of the impact of World War I on the Clinton County Community. With Helen Nerska based on research by CCHA Past President Noel Stewart.
A Jury of Your Peers. Women received the right to vote across the nation in 1920 but not the right to be on a jury until years later. Learn the struggle for and gradual acceptance of women on juries. With Helen Nerska.
History of Standish, New York. With author and historian Marissa Dandrow. Explore the history of Standish through its industries, businesses, residents, population changes and immigration, major events, and the everyday stories that made it one of the Adirondacks' most fascinating iron villages. Includes some of the history of Standish's Black and multiracial residents.
The Booming Blueberry Business on the Altona Flat Rock (1850-1957)
Did you know that for more than a century, local families traveled to the Altona Flat Rock each summer to harvest wild blueberries and earn extra income? These prized berries were shipped to markets in Boston, New York City, and beyond, helping to create a thriving seasonal industry in the North Country. What made the Altona blueberries so special, and why did this once-booming business disappear in 1957? Join local history enthusiast Steven Frederick as he shares the fascinating story of the mighty blueberry and its important role in our region's past.
Manufacturing in Clinton County Since 1831
Long before Clinton County became a modern manufacturing center for aerospace and transportation industries, local factories and workshops were producing goods that helped build America. This engaging presentation explores nearly two centuries of manufacturing history, featuring products such as typewriters, sewing machines, automobiles, horse nails, apple barrels, fine furniture, and more. Through rare historic photographs, including black-and-white glass plate negatives from the Clinton County Historical Association, attendees will discover what life was like for early factory workers, how industries evolved over time, and the often challenging and hazardous conditions they faced. Join local history enthusiast Steven Frederick for a fascinating pictorial journey through Clinton County's industrial past.
History of The Chateaugay Railroad. With author and historian Marissa Dandrow. The Chateaugay Railroad was the first railroad to reach the heart of the Adirondacks, and it played a major role in boosting Adirondack tourism. It began as an industrial narrow-gauge railroad that was well suited to the area's mountainous terrain. The ride itself was a thrill, winding around mountains and lakes, traveling in every direction on the compass to maintain a feasible grade. The railroad connected the Chateaugay ore bed to Plattsburgh, where ore barges and D&H trains could transport the products throughout the United States. It also brought workers, supplies, and goods to the remote villages of the ore bed and Chateaugay Woods. Starting in 1880, the railroad capitalized on Adirondack tourism, becoming a powerhouse for both pleasure and health tourism. It reached Loon Lake in 1886, Saranac Lake in 1887, and Lake Placid in 1893. Come learn more about this history-making railroad.
