FIG. 122.—Diagram showing enlarging with and without distortion: _A_, enlarging without distortion; _B_, distortion for rectification of print, by inclining printing surface; _C_, distortion, for rectification of print, by inclining both negative and printing surface.] Before putting them in alcohol it is advisable to squeegee all the surface water from the prints. This may be expeditiously done by removing them in mass from the final wash water upon a large ferrotype plate, and either running the plate and prints together through a wash wringer with light pressure, or covering the whole with a sheet of blotting paper and pressing out the water underneath by means of a rubber squeegee vigorously applied. For base work one of the modern automatic print-drying machines used in commercial photography would be desirable. Glossy surfaces are given prints by the usual ferrotype plate method. But this is too time-consuming for war practice, and besides has but doubtful advantage where papers of the glossy type are chosen. VI PRACTICAL PROBLEMS AND DATA CHAPTER XXV SPOTTING “_Spotting_,” as distinct from mapping or from the photography of continuous strips, is the photography of a definite individual objective. In military work spotting or “pin pointing” includes the photography of particular trenches or pivotal points in a trench system before an attack (Fig. 123), of roads or bridges along which an advance must pass (Fig. 124), of batteries or big guns which are the subject of artillery fire (Fig. 125), both before and after their bombardment (Fig. 126), of gun puffs or exploding bombs (Fig. 131). The technique of spotting consists largely in getting properly over the target and then securing the exposure at just the right moment. This is chiefly a question of proper piloting; but the aid which can be offered to the pilot by camera auxiliaries designed particularly for spotting needs is very large.