74 Scientific Intelligence. 



II. Geology and Mineralogy. 



1. Examination of Deposits obtained from borings in the Nile 

 Delta. — Prof. John W. Judd has given to the Royal Society a 

 report on a series of specimens of the deposits of the Nile Delta, 

 obtained by boring operations, a continuation of similar work the 

 results of which were published in 1885. The later borings here 

 described were made at Zagazig, and were carried down 100 feet 

 with a 5-inch pipe, and nearly 100 leet farther with a 4-inch 

 pipe. The work was then discontinued, but renewed again a year 

 later, and by vigorous efforts carried to a depth of 339^- feet with 

 a 3-inch pipe, and from this point a rod was pushed down 

 5 feet 6 inches farther, so that the exploration attained a total 

 depth from the surface of 345 feet, or 319 feet below the sea 

 level, without reaching solid rock. 



It is stated that from the surface to a depth of 115 feet the 

 strata passed through in the Zagazig boring closely resembled 

 those already reported upon as occurring in the earlier borings, 

 and consisted of alternations of desert-sand and Nile-mud. The 

 alluvial mud, which prevails from the surface to a depth of 20 

 feet, contains numerous small tubular and knot-like bodies, doubt- 

 less formed by the deposition of calcium carbonate on the root- 

 lets of plants. These bodies become fewer at greater depth and 

 are absent in the clay from depths between 75 and 92 feet. 

 At this level an indurated alluvial mud was found in irregular 

 masses of concretionary argillaceous limestone. 



A sudden change in the deposits was found at a depth of 116 

 feet ; here beds composed of a mass of coarse sand and shingle 

 were met with and continued to a depth of 151 feet. At the 

 latter depth a band of yellow clay was passed through, two feet in 

 thickness, and under it sand and shingle beds prevailed till the 

 lowest depth reached, 345 feet. Specially coarse shingle beds 

 were found at the following depths : 121, 160, 175, 190, 208, 250, 

 265, and 270 feet. In some of these shingle beds the fragments, 

 which were usually well rounded — often, indeed, perfect pebbles — 

 were very coarse, the fragments being of all sizes up to that of a 

 hen's egg. 



The general results obtained are similar to those from a boring 

 made at Rosetta in the summer of 1885 and carried to a depth of 

 153 feet. The sudden change from the blown sand and alluvial 

 mud of the Nile delta to masses of shingle and sand noted at a 

 depth of 115 feet at Zagazig was met with at a depth of 143 feet 

 at Rosetta, showing that the surface of the old gravel deposits is 

 very uneven. 



A careful search was made for fossils, especially in the clays, 

 in order, if possible, to fix the geological age of the deposits 

 underlying those of the delta ; but this attempt was unsuccess- 

 ful. The pebbles consisted largely of quartz and chalcedony, and 

 sandstones, all of which, it is suggested by Dr. K. von Zittel of 

 Munich, may have been derived from the Gebel Achmar Sand- 



