The dark tan leather album, no bigger than an A4 notebook, is beautifully decorated. Plump cherubs sit amongst knots of foliage that climb the book's border. At the centre, an exotic botanical arrangement spews from a vase.

It's clearly old. Inside the pages are crumbly at the edges and even museum curators have to handle them with gloved hands.

But it's what is artfully arranged on these pages that has caught the attention of historians.

Essentially a time capsule, the dried, pressed seaweed samples inside provide a glimpse into the botanical life of Port Phillip Bay's waters between 1859 and 1882.

The seaweed album holds more than 200 samples of the marine plants, affectionately described as "flowers of the sea" by the album's creator.

On some pages a single branch of seaweed reaches out to the edges. On others, there are up to 11 specimens. Some have fronds as delicate as lacework, others are as chunky as old gum leaves.

A poem, stamped in red ink, on the inside cover is charming. It begins "Call us not weeds, we are flowers of the sea for lovely and bright and gay tinted are we."

The National Museum Australia in Canberra purchased the fragile album in 2013 for $3500. It is one of just 30 known seaweed albums in the country and will go on public display for a fortnight from April 8.

It took the museum's artist in residence Julie Ryder six months of work last year to solve the mystery of who was behind the album.

"Personally I was convinced that this was going to be by a woman," Ms Ryder said. "The collages, the poem and the beautifully decorated cover; it's all highly feminised."

National Museum Australia curator Catriona Donnelly said collecting seaweed was a fashionable pastime for middle class women in the 19th century. Seaweed and foreshore designs were prominent on textiles, china and wallpaper at the time.

"It was a real craze," she said. "It's hard to imagine seaweed being such a popular thing but the study of natural history was seen as a respectable way to fill your leisure time."

Ms Ryder also thought it was compiled by a citizen scientist - the album isn't organised by theme, species or timeframe but by aesthetics. There is the odd botanical name, date and location of collection - neatly recorded by hand.

After comparing the Port Phillip seaweed album with two held by Melbourne's Royal Botanic Gardens' Herbarium Ms Ryder was proved wrong.

"I got the shock of my life because at least two of their albums are by the same collector," she said. "They look exactly the same and the handwriting and collections are the same and the dates match up."

Ms Ryder said the Port Phillip Bay album was made by prolific collector Charles Morrison. With the museum, she has issued a national callout for information on the Glasgow-born collector, who married a woman in Northern Ireland before migrating to Victoria in the 1850s. He lived in Collingwood and Fitzroy and died in Ascot Vale.

Ms Ryder believes he made the albums for his niece, Georgina Thomasina Maxwell, and granddaughters Jessie Morrison Magee and Jane Augusta Magee.

The creator of at least 10 albums Ms Ryder hopes that if she can locate Charles Morrison's descendants, she can learn more about the man and perhaps even uncover more albums.

"I feel like I know him but at the same time he has remained elusive," Ms Ryder said.

Ms Donnelly said the album was more than just a rare object. Being a record of the Port Phillip seaweed population in the 1850s to the 1880s – starting just 20 years after Melbourne was settled – it could yet adopt a greater historic and scientific significance.

"It is a snapshot in time which could be used in the future as there are possibly specimens in there that are no longer found in the bay," she said. "Its significance overtime will probably increase."

The Port Phillip album will be one of two seaweed albums to go on display. The second album is dated 1836 and contains seaweeds from Port Arthur, Tasmania. It was created by Lady Catherine Frere, daughter of Sir George Arthur governor of Van Diemen's Land.

"With the rise in ocean temperatures causing a threat to seaweed species in their oceans, these albums become quite important historical documents even though they are not from a scientific viewpoint," she said. "They could still be used as a reference for the species found in those places at that particular time."

People who think they have any information about the Victorian album should go to the NMA website and follow the seaweed album links to where they can lodge information with the duty curator.

Julie Ryder will outline her findings at a free public seminar in Canberra at the Australian National University on April 20.