Page:Blackwood's Magazine volume 144.djvu/566

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560
The Romance of State-Mapping.
[Oct.

place to see the National Survey through the difficulties that at this period beset it.

The consequences to the work, too, of all this chopping and changing, were simply disastrous. For fifteen months in 1853-54 the director of the Survey was without any orders as to the particular scale or proportion of actual ground dimensions the maps were to be drawn upon: the result of which was, that there was an accumulation at the end of the time of nearly a million of acres of work surveyed but not laid down on paper. Well might Sir Henry complain "of the extreme inconvenience to which we were subjected, and how thoroughly all our arrangements were upset by the perpetual changing from one scale to another."[1] Again, "the great drawback to the Survey has been the frequent change of orders relative to it." And again, in a note written at the end of June 1857, evidently in disgust, and appended to his Report for 1855-56, he says: "The decision of the House of Commons, on the 18th instant, has rendered nugatory all the arrangements we have made for making the plans on the 25-inch scale, and the reductions from them: and, after a seven years' discussion, we revert to precisely the same position we were in when the Treasury minute of 1st October 1840 was issued." In 1857-58 the cutting down of the Survey grant some £30,000 compelled James to discharge upwards of 1000 men (nearly half his force), "and the progress of the Survey," he writes, "has in consequence been greatly retarded."

In 1857, Colonel James became head of the Topographical and Statistical Depot of the War Office, and remained in this position till the severance of the Ordnance Survey from the War Department in 1870. This considerably added to his labours. He was the author of several brochures on different scientific subjects germane to the work of the Survey – e.g., projection of maps, meteorological observations, antiquities, &c. But the principal study with which the name of Sir H. James will always be associated was his successful application of photography to the production of maps, without which auxiliary it would have been a simple impossibility to keep pace with the ever-increasing volume of map publications on all the various scales. The great diminution of cost as well as increase of accuracy in copying by this over any other known process were placed beyond a doubt by the committee appointed to investigate the subject under the able presidency of Sir Roderick Murchison. It was feared that error might arise in a photographically reduced copy of a map by reason of mechanical distortion. But the committee set this apprehension at rest by declaring, as the result of their inquiry, "that the greatest deviation in any part of the plans from perfect accuracy does not amount to 1/400 part of an inch;"[2] quantity quite inappreciable, and much less than the error due to contraction and expansion of the paper the maps are printed on.

Of all our branches of work, none attracted more attention from foreign Governments than those connected with the reduction of maps by photography and photo-zincography. The Spanish

  1. Select Committee of 1861 – Minutes of Evidence, Q. 18.
  2. Report of Committee on "Reduction of the Ordnance Plans by Photography," 1859.