At first Hansie was speechless with admiration; then she threw her arms round her mother and hugged her vigorously.
"Really, mother," she exclaimed, "I am proud of you. How we shall be able to dupe 'Miserable Renegade' now!"
The full importance of this discovery was not realised at the time, for all their smuggling had hitherto been carried on merely for pleasure and they had had no information of any importance to communicate to their friends across the seas; but, in the light of after-events, they realised that they had been led to make their preparations and to have their methods in full working order before the time came to use them in conveying dispatches from the Boer Secret Service to President Kruger in Holland.
They were now in the possession of a scheme which defied detection, and the next thing to be done was to inform some distant conspirator of this valuable discovery and instruct him in the use of it.
That this could not be done through the post, my reader will understand, and as reliable opportunities were becoming more rare, Hansie had to wait some months and to possess her soul in patience until at last some trusted friend, leaving the country, could be persuaded to convey the important instructions.
When and how they were eventually sent I cannot tell with positive certainty. There is a difference of opinion on this point between Mrs. van Warmelo and her daughter, and there is no way of settling the dispute, because Hansie's diary contains no word about the White Envelope, for reasons which it will hardly be necessary to explain.
Mrs. van Warmelo says the instructions were dispatched in a false double-bottom of an ordinary safety match-box. Hansie thinks they were either hidden behind a photo-frame or in a tin of insect-powder, both these methods having been employed on various occasions, but at present we are only concerned with the fact that the instructions reached their destination safely, and from that day until the end of the war a gloriously free and uninterrupted communication was kept up between Harmony and Alphen and one spot in the north of Holland, of which we shall hear more as our story unfolds itself.
Further experimenting showed that the lemon-juice became visible after a few days when written on certain papers, while on others there was nothing to be seen after many weeks, and this danger was immediately communicated to Holland as a very serious one, for it stands to reason that the danger connected with the sending of the White Envelope from South Africa was nothing compared to the danger of receiving one and having it censored three weeks after it had been written.
One had to keep in mind that letters leaving the country would be censored immediately and would not be subjected to further scrutiny in Europe, whereas letters for South Africa ran every risk of being betrayed on examination, after a three-weeks' journey by land and sea.
When the smuggled instructions were well on their way, the first White Envelope was written to Holland, and carelessly thrust amongst a pile of other letters by the quaking Hansie when next she handed her mail to "Miserable Renegade."