Forty Centuries of Ink / Or, A chronological narrative concerning ink and its backgrounds, introducing incidental observations and deductions, parallels of time and color phenomena, bibliography, chemistry, poetical effusions, citations, anecdotes and curiosa together with some evidence respecting the evanescent character of most inks of to-day and an epitome of chemico-legal ink.

by David Nunes Carvalho

" '4. Do you consider carbon ink the only permanent ink?

" '5. What inks of your manufacture would you advise against using for a permanent record?

" '6. Do you advise generally against the inks known as writing fluids, when permanency is the first requisition?

" '7. Do you manufacture a writing fluid?

" '8. Do you consider it safe to add water to ink intended for permanent record, which has grown thick by exposure to the air?

" '9. Do you believe that the obliteration of ink is ever due to the chemicals left in the paper? (This question has been asked of the paper manufacturers also.)

" '10. Do you consider it safe to mix inks without knowing to what chemical group the inks so mixed belong?'

"Replies were received from twenty-two manufacturers. Several of the inks in the market, though bearing the name of certain persons, were found to be manufactured for them by manufacturers who had already answered the questions. Their replies were, therefore, not considered.

"To the first question, 'Do you consider it safe to use for a permanent record aniline inks!' the unanimous answer was decidedly no. Aniline black is absolutely permanent, but as it is not yet known how to render it soluble in water, it has not been much used in ink.

"To the inquiry in regard to logwood inks, nearly all answered no, and most of those who did not qualified their answers to such an extent as to imply distrust.