In due time the expedition reached Kouka where it remained for a while, as Dr. Barth had gone on to Timbuctoo. The return of the chief being uncertain Dr. Vogel explored the country in the vicinity of the lake, taking with him corporal Maguire. Corporal Church was left to carry on the meteorological observations. Contrary to expectation, Dr. Barth, who had been reported dead, returned to Kouka, and soon after, corporal Church accompanied him home. Whatever services may since have been conducted by Dr. Vogel—of which no account has been communicated to the corps, it is proper, nevertheless, to record to the credit of the corporal the very kind terms in which, under date the 4th December, 1855, the doctor wrote of him to the Consul-General at Tripoli:— “I beg to recommend to your special notice my faithful companion John Maguire, royal sappers and miners, who has, notwithstanding a serious indisposition under which he suffered in the beginning of our journey, used every exertion to promote the object of the expedition, and behaved in the most praiseworthy manner.” For his services corporal Church received a gift of 15_l._ from the foreign minister and a silver watch from the Royal Geographical Society. The small party under Captain Owen, R.E., at Marlborough House, was increased in February to five rank and file. On the completion of the referential arrangement of the correspondence and documents connected with the Great Exhibition, they were attached in May to the department of practical science and art, under the superintendence of Mr. Henry Cole. Since the transfer they have been engaged in services of a very miscellaneous character, embracing the distribution to national and public schools of examples and models for teaching elementary knowledge, form, and colour, mounting and tinting examples and prints, preparing models, &c., and officiating as clerks and draughtsmen in the offices at Marlborough House. Corporal Mack, in addition to his ordinary duties, produced two or three plans of an interesting character. In arranging some dietary tables Dr. Lyon Playfair engaged the assistance of the corporal. The ingredients used as food, extending to twenty-three substances, having been subjected by the professor to analysis, required to be classified into a simple and consistent arrangement. This the corporal effected by means of an ingenious diagram in colours. Dr. Playfair was well pleased with the illustration, and when at a meeting of the Royal Society, to which the corporal had the honour of being invited, the professor announced his intention of publishing it for the use of schools, the promise was received with applause. True to his intention, Professor Playfair afterwards produced the plan in colours on a very large scale, and gave it a distribution as wide as the United Kingdom. On the 8th June, 1853, the diagram was exhibited at the Mansion-house, and attracted much attention. A reduced plan of the