EXPLANATION OF THE PLATES. 375 



injecting too little water into them when 

 their speed is great, thereby deteriorating 

 the vacuum and reducing the power of 

 the engines, and that at the time when 

 the greatest power is required. 



11. In injection engines, the proper In the patent engines, the boilers are 

 supply of water to the boilers is depend- never liable to be burnt down or injured 

 ent upon and entirely at the mercy of by the water becoming in them, by acci- 

 the engineers, from whose negligence such dent or by the carelessness of engineers, 

 serious accidents arise as those of the ex- too low, for as every cubic foot of water 

 plosion of the two Hull steam vessels, the which is converted into steam is by con- 

 Union and Victoria, and many others, by densation reconverted into precisely the 

 which a most serious loss of life has taken same quantity and returned to the boil- 

 place and great injury has been done to ers, the water is always kept in them at 

 the reputation of steam navigation. exactly the same height without any at- 

 tention on the part of the engineer. 



12. In injection engines, the vacuum is In the patent engines, a superior va- 

 injured by the air which is in mechani- cuum is obtained, owing to no air being 

 cal combination with the injection water introduced into the condensers, and to the 

 being conveyed by it into the condenser, condensation being more perfect than can 



be effected by injection." 



"ADVANTAGES APPERTAINING TO THE PATENT IMPROVEMENTS. 



"First, from the various causes above mentioned, a saving of at least one third part 

 of the fuel is effected in the patent engines, or in other words injection engines con- 

 sume half as much more fuel as the patent engines. 



Second, for every ton of coal that is saved, a ton of profitable freight may be sub- 

 stituted. 



Third, as vessels with engines to which the patent improvements are applied 

 make their passages nearly as quick in stormy as in fine weather, and as they do 

 not require during or at the end of their passages, however numerous, any blowing- 

 out or cleaning of the boilers, to occasion delays, every vessel is capable of making- 

 more passages and of becoming in that ratio more profitable. 



Fourth, as boilers supplied with pure distilled water will endure a much greater 

 length of time than those in which salt water is used, not only is the annual expense 

 of the boilers greatly diminished, but the loss of the time of the profitable use of the 

 vessel during the taking out of old boilers and the replacing them with new ones 

 is also avoided, to say nothing of the breaking up of the decks and other expenses 

 attending the business. 



