To this the Board of Trade replied, on April 13, that Colonel Yolland had been instructed to visit the tunnel works "entirely out of regard to the very urgent and grave question raised in your letter ... respecting the ventilation of the boring" and that the department was finding it difficult to understand why Colonel Yolland's visit to the tunnel should be postponed. Sir Edward's answer to this was to invite Mr. Chamberlain down into the tunnel personally, so that Sir Edward could "show and explain everything," since "until you have seen, and had explained to you, on the spot as Mr. Gladstone did and had, and as we hope the Duke of Edinburgh will next Tuesday, the nature and condition of our works, it is, in my humble judgement, impossible to discuss the question with exactitude." He said nothing about the possibility of Mr. Chamberlain's or the Duke and Duchess of Edinburgh's being asphyxiated in the tunnel. Mr. Chamberlain declined the invitation; he said he had ordered Colonel Yolland down to Dover immediately to report on the tunnel. But Colonel Yolland didn't get down into the tunnel to make an inspection that month. Some impediment, some unanticipated difficulty always seemed to arise when things appeared to be about to straighten themselves out. By the beginning of May, the Board of Trade, still trying, flatly informed Sir Edward that Colonel Yolland and Walter Murton, its solicitor, would inspect the tunnel workings on May 6. But on May 4 the general manager of the South-Eastern Railway replied that "Sir Edward Watkin wishes me to say that he regrets very much that it will be quite impossible to arrange for such inspection to take place on that date." He suggested that Sir Edward could arrange it for the 13th. The Board of Trade, replying immediately, insisted on its taking place "not later than Wednesday next." That letter was met with the answer that "Sir Edward Watkin is at present out of town, and is not expected to return until early next week." He must have stayed out of town quite a while, because the Board of Trade heard nothing from the company until May 18, when the directors of the company, writing jointly, told the department that while they acquiesced in the request of Colonel Yolland and Mr. Murton to visit the tunnel, unfortunately "the machinery is under repair," and as a consequence "it would not be ... safe for those gentlemen to go down the shaft." However, the directors added, hopefully, they felt sure that "by working the machinery, air compressors, and pumping engines for a few days and nights" their engineers could get everything in order for a proper tour of inspection. On May 24 Mr. Murton tried again. He wrote the tunnel proprietors, notifying them that "Colonel Yolland and myself propose to inspect the tunnel works on Saturday next the 27th instant." But the company's reply to the letter was regretful. It said that "the repairs to the winding engine cannot be completed until after Whitsuntide."